feat(module): Add an option to specify a library name prefix

[vikerman]

Add a new option libraryNamePrefix which will add a prefix to the generated library names.

This is useful when the library name generated by basePath is removing some part of the library name that's needed.

Ex. For Angular 2 - basePath=modules/angular2, libraryNamePrefix=angular2 would still generate the right library names with "angular2.xxx.xxx"

[mprobst]

LGTM