Update src/main/java/net/sf/alchim/spoon/contrib/maven/AbstractSpoonMojo.java

given the project basedir, because it gives some issues when using the undeterministic '.' as source directory.
Update src/main/java/net/sf/alchim/spoon/contrib/maven/MavenEnvironment.java

Override getSourcePath() to return mavenProject.baseDir instead of using undeterministic '.'
Merge pull request #1 from yvesdm/master

Fix a problem in getSourcePath()