Patches for JBuilder plugin

• The plugin attempts to find JBuilder's "HOME" directory where it will read
  the user's default project properties file.
• The JBuilder "HOME" directory is also where library files are generated.

This is a major rewrite of the JBuilder plugin that keeps backwards compatibility, while adding much more complete generation of project and library files. Some of the ideas have been borrowed from the latest versions of the IDEA and Eclipse plugins. Here is a short summary that covers some of the highlights:

• The plugin attempts to find JBuilder's "HOME" directory where it will read the user's default project properties file. The JBuilder "HOME" directory is also where library files are generated.

• When you generate a JBuilder project file, the plugin iterates through its dependencies. For each dependency, a library definition file is generated for the dependency jar in the local repo. This dependent library file is generated if, and only if, the library file does not already exist or the library file was previously generated the same way (as a dependency on a jar in the local repo).

• The previous point means that when you generate a jbuilder library
  definition file directly from a Maven project (using the jbuilder:generate-library goal) you will replace any previous definition of the library that was generated as a jar-only dependency with a library definition that references both the source and class files.

• For library definitions that remain jar-only references to the local repo, you can specify a path to the corresponding source code via properties.

• Support has been added for generating JBuilder application and applet runtime configurations from properties.

• Any resources are added to the JBuilder project source path.

• Using an optional property, you can specify a list of explicit files that will be included in the JBuilder project if they exist. The default list are project.xml, project.properties, and maven.xml.