Porting of gradle changes from master.

samples/cas/cas.gradle

@@ -2,11 +2,8 @@ apply id: 'war'
 apply id: 'jetty'
 
 dependencies {
-//    providedCompile 'javax.servlet:servlet-api:2.5@jar'
-
     runtime project(':spring-security-core'),
             project(':spring-security-web'),
             project(':spring-security-config'),
-//            project(':taglibs'),
             'log4j:log4j:1.2.15@jar'
 }

samples/contacts/contacts.gradle

@@ -5,10 +5,10 @@ apply id: 'jetty'
 
 dependencies {
     providedCompile 'javax.servlet:servlet-api:2.5@jar'
+
     compile project(':spring-security-core'),
             project(':spring-security-acl'),
             "org.springframework:spring-aop:$springVersion",
-            "org.springframework:spring-core:$springVersion",
             "org.springframework:spring-beans:$springVersion",
             "org.springframework:spring-context:$springVersion",
             "org.springframework:spring-jdbc:$springVersion",

samples/tutorial/tutorial.gradle

@@ -5,8 +5,8 @@ apply id: 'jetty'
 
 dependencies {
     providedCompile 'javax.servlet:servlet-api:2.5@jar'
+
     compile project(':spring-security-core'),
-            "org.springframework:spring-core:$springVersion",
             "org.springframework:spring-beans:$springVersion",
             "org.springframework:spring-web:$springVersion",
             "org.springframework:spring-webmvc:$springVersion",