* Add new functions to communicator helper to return the user, password, host, based on the communicator used.
This implementation can help then generalize the provisioeners later on.
* Update null builder checks to utilize the new functions and check for ANY hostname or user or password
* Update builder to user any hostname
When debugging a build (or maintaining an existing packer template), teach `packer build -debug` how to step through individual `boot_command`s in order to triage the packer template.
When debugging a build (or maintaining an existing packer file), teach `packer build -debug` how to step through individual `boot_command`s in order to triage the packer template.
This fixes building `packer` with Go >1.6. From https://golang.org/cmd/link/:
```
-X importpath.name=value
Set the value of the string variable in importpath named name to value.
Note that before Go 1.5 this option took two separate arguments.
Now it takes one argument split on the first = sign.
```
When debugging a build (or maintaining an existing packer file), teach `packer build -debug` how to step through individual `boot_command`s in order to triage the packer file.
When debugging a build (or maintaining an existing packer file), teach `packer build -debug` how to step through individual `boot_command`s in order to triage the packer file.
```
==> vmware-iso: Typing the boot command over VNC...
==> vmware-iso: Pausing after run of step 'boot_command[0]: <enter><wait>'. Press enter to continue.
==> vmware-iso: Pausing after run of step 'boot_command[1]: <enter><wait>'. Press enter to continue.
==> vmware-iso: Pausing after run of step 'boot_command[2]: freebsd-vagrant<enter><wait>'. Press enter to continue.
==> vmware-iso: Pausing after run of step 'boot_command[3]: <down><spacebar>'. Press enter to continue. ^C
```
Chris Bednarski
Robert Deusser
Vasiliy Tolstov
Christopher Boumenot
Gonzalo Peci
Avi Deitcher
Hidekazu Tanaka
David J. Felix
Sean Chittenden