Definition of the options for SBT in project/BuildPlugin.scala:
1/ Still need to add the special settings for test in order to execute
scalac using the plugin.
2/ Modification of the structure of the project to use the best
practices of sbt.
Removal of some garbage produced by the use of an example (boxer)
to test the proper use of SBT constraints.
Merge branch 'master' of https://github.com/aghosn/ASTpersistence