Added support for different types of artifacts
Artifact type is being figured out properly.
Merge pull request #1 from tomasherman/master

{jar,doc,src} support added
Merge branch 'master' of github.com:freekh/adept into ivy_fixes

Conflicts:
	src/main/scala/adept/Adept.scala
	src/main/scala/adept/ivy/Ivy.scala
	src/main/scala/adept/models/Artifact.scala
	src/main/scala/adept/models/Module.scala
	src/main/scala/adept/operations/Add.scala