Integration of mindoc in mindc.
-Use org.ow2.mind.cli instead of org.apache.commons.cli
-Add .gitignore file in the root.
-Add README_DOC.txt file.
-Remove README.txt file.
-Put commons-io and mindoc jar files in the "ext" compiler folder.
-Use -o instead of -d for output path.
-WARNING : Disable the doc generation test in the pom.xml.
-This test must be transfer to a specific continuous integration task.