docs(cleanup): fix bad h3 markup and normalize headings

Closes #5341

modules/angular2/src/common/directives/ng_if.ts

@@ -18,7 +18,7 @@ import {isBlank} from 'angular2/src/facade/lang';
  * </div>
  * ```
  *
- *##Syntax
+ * ### Syntax
  *
  * - `<div *ng-if="condition">...</div>`
  * - `<div template="ng-if condition">...</div>`

modules/angular2/src/common/directives/ng_style.ts

@@ -15,7 +15,7 @@ import {isPresent, isBlank, print} from 'angular2/src/facade/lang';
  * corresponding element styles are updated based on changes to this object. Style names to update
  * are taken from the object's keys, and values - from the corresponding object's values.
  *
- *##Syntax
+ * ### Syntax
  *
  * - `<div [ng-style]="{'font-style': style}"></div>`
  * - `<div [ng-style]="styleExp"></div>` - here the `styleExp` must evaluate to an object

modules/angular2/src/common/forms/directives/ng_control_group.ts

@@ -18,7 +18,7 @@ const controlGroupProvider =
  *
  * This directive can only be used as a child of {@link NgForm} or {@link NgFormModel}.
  *
- * # Example ([live demo](http://plnkr.co/edit/7EJ11uGeaggViYM6T5nq?p=preview))
+ * ### Example ([live demo](http://plnkr.co/edit/7EJ11uGeaggViYM6T5nq?p=preview))
  *
  * ```typescript
  * @Component({

modules/angular2/src/common/forms/directives/ng_form.ts

@@ -23,19 +23,19 @@ const formDirectiveProvider =
  * If `NgForm` is bound in a component, `<form>` elements in that component will be
  * upgraded to use the Angular form system.
  *
- *##Typical Use
+ * ### Typical Use
  *
  * Include `FORM_DIRECTIVES` in the `directives` section of a {@link View} annotation
  * to use `NgForm` and its associated controls.
  *
- *##Structure
+ * ### Structure
  *
  * An Angular form is a collection of `Control`s in some hierarchy.
  * `Control`s can be at the top level or can be organized in `ControlGroup`s
  * or `ControlArray`s. This hierarchy is reflected in the form's `value`, a
  * JSON object that mirrors the form structure.
  *
- *##Submission
+ * ### Submission
  *
  * The `ng-submit` event signals when the user triggers a form submission.
  *

modules/angular2/src/common/forms/directives/ng_form_control.ts

@@ -49,7 +49,7 @@ const formControlBinding =
  * }
  *  ```
  *
- *##ng-model
+ * ###ng-model
  *
  * We can also use `ng-model` to bind a domain model to the form.
  *

modules/angular2/src/common/forms/directives/ng_model.ts

@@ -22,7 +22,7 @@ const formControlBinding =
 /**
  * Binds a domain model to a form control.
  *
- *##Usage
+ * ### Usage
  *
  * `ng-model` binds an existing domain model to a form control. For a
  * two-way binding, use `[(ng-model)]` to ensure the model updates in

modules/angular2/src/common/forms/directives/validators.ts

@@ -33,7 +33,7 @@ const REQUIRED_VALIDATOR =
  * A Directive that adds the `required` validator to any controls marked with the
  * `required` attribute, via the {@link NG_VALIDATORS} binding.
  *
- * # Example
+ * ### Example
  *
  * ```
  * <input ng-control="fullName" required>
@@ -76,4 +76,4 @@ export class MaxLengthValidator implements Validator {
   }
 
   validate(c: Control): {[key: string]: any} { return this._validator(c); }
-}
+}

modules/angular2/src/common/forms/model.ts

@@ -245,7 +245,7 @@ export abstract class AbstractControl {
  * `Control` is one of the three fundamental building blocks used to define forms in Angular, along
  * with {@link ControlGroup} and {@link ControlArray}.
  *
- * ##Usage
+ * ## Usage
  *
  * By default, a `Control` is created for every `<input>` or other form component.
  * With {@link NgFormControl} or {@link NgFormModel} an existing {@link Control} can be
@@ -421,7 +421,7 @@ export class ControlGroup extends AbstractControl {
  * along with {@link Control} and {@link ControlGroup}. {@link ControlGroup} can also contain
  * other controls, but is of fixed length.
  *
- * ##Adding or removing controls
+ * ## Adding or removing controls
  *
  * To change the controls in the array, use the `push`, `insert`, or `removeAt` methods
  * in `ControlArray` itself. These methods ensure the controls are properly tracked in the

modules/angular2/src/common/forms/validators.ts

@@ -29,7 +29,7 @@ export const NG_ASYNC_VALIDATORS: OpaqueToken = CONST_EXPR(new OpaqueToken("NgAs
  * controls and returns a {@link StringMap} of errors. A null map means that
  * validation has passed.
  *
- * # Example
+ * ### Example
  *
  * ```typescript
  * var loginControl = new Control("", Validators.required)

modules/angular2/src/common/pipes/number_pipe.ts

@@ -66,7 +66,7 @@ export class NumberPipe {
  * Formats a number as local text. i.e. group sizing and separator and other locale-specific
  * configurations are based on the active locale.
  *
- *##Usage
+ * ### Usage
  *
  *     expression | number[:digitInfo]
  *
@@ -101,7 +101,7 @@ export class DecimalPipe extends NumberPipe implements PipeTransform {
  *
  * Formats a number as local percent.
  *
- *##Usage
+ * ### Usage
  *
  *     expression | percent[:digitInfo]
  *
@@ -127,7 +127,7 @@ export class PercentPipe extends NumberPipe implements PipeTransform {
  *
  * Formats a number as local currency.
  *
- *##Usage
+ * ### Usage
  *
  *     expression | currency[:currencyCode[:symbolDisplay[:digitInfo]]]
  *

modules/angular2/src/common/pipes/slice_pipe.ts

@@ -16,7 +16,7 @@ import {Pipe} from 'angular2/src/core/metadata';
  *
  * The ending index of the subset to return is specified by the optional `end` parameter.
  *
- *##Usage
+ * ### Usage
  *
  *     expression | slice:start[:end]
  *