Update GridAccess.py

- add function to clean directory
- Optimization of remove outpudata function
Update dirac-glast-pipeline-get-logfile.py

- Bug Fix
- minor optimization
Create InstallSoftware.py

- Installation script on site 
- Tag Registration only in DB (not on glite)
Update dirac-glast-softwaretag-cli.py

- add function do_preinstall
- add function do_installonsite
Update GridAccess.py
Update InstallSoftware.py

Put the rsync server Address in the Dirac CS.
Update dirac-glast-pipeline-get-logfile.py

Path of the file storing the id of the Jobs handled in the CS
Merge pull request #90 from vrolland/master

Lasts commits from vrolland