TEIIDDES-2137: Migrate jar libraries to their own plugin and download th...

...em

* Creates a new webservice.lib plugin for holding and handling access to
  the rest and soap war library dependencies. Instead of these jars being
  held in the codebase, download them using maven instead.

* Separate plugin required to avoid having to build all the teiid designer
  maven dependencies.

* DefaultWebArchiveBuilderImpl
* RestWebArchiveBuilderImpl
 * Fetches the library dependencies from the webservice.lib plugin