5.10.0 -- Add .inc.css support and _hoplon jar resources

- Hoplon has supported the convention of using the `.inc.js` file
  extension to indicate to the compiler JavaScript files to prepend to
  the compiled output file. These include files may be provided anywhere
  on the classpath (i.e. in dependency Jars in Maven or in the source
  directories of the project).

- Hoplon now supports the following additional file extensions:

  .inc.css     CSS stylesheets to be automatically loaded into the page.
  .lib.js      Google Closure JavaScript libraries to compile with the
               application.

- Additionally, Hoplon now provides a facility for packaging resources
  in Jar dependencies. Create a directory named `_hoplon` in which to
  store the resources, at the root of a source directory. These
  resources will be copied to the output directory automatically.

  **** NOTE ***

  All files are included in dependency order (i.e. dependents are included
  before the files that depend on them are) and sorted lexically within
  each Jar file (i.e. the .inc.js files within a given Jar file are ordered
  by file name, but the Jars themselves are ordered by their dependency
  relationships).