Eclipse IDE support

[elzibubble]

When using this plugin in Eclipse with m2e, you get "Plugin execution not covered by lifecycle". This makes the plugin unusable in Eclipse; even if you add a custom lifecycle mapping, the plugin continually recompiles. Some small changes to the plugin will prevent this, allowing Eclipse devs to benefit from your work.

There is a good page here: http://wiki.eclipse.org/M2E_compatible_maven_plugins
which describes the steps necessary. Essentially:

1. Add a small XML file
2. Use BuildContext for file operations

You can see an example of the XML here: https://github.com/marceloverdijk/lesscss-maven-plugin/blob/master/src/main/resources/META-INF/m2e/lifecycle-mapping-metadata.xml

The page has some examples of using BuildContext, but here's a real example: https://github.com/marceloverdijk/lesscss-maven-plugin/blob/master/src/main/java/org/lesscss/mojo/CompileMojo.java