Moved to nice-sbt-settings plugin
Changed type of leterateFile/Dir: now it returns error messages if any
Added file name to parsing error messages
Merge branch 'release/v0.3.0' into feature/index

Conflicts:
	README.md
	src/main/scala/Literator.scala
	src/test/scala/TestCode.scala
Added index generation
Added index to the generated markdown; changed interface to use File/Path everywhere