create the archive from a Git branch

git-svn-id: http://piwigo.org/pem_svn/trunk@376 d4d6b01b-5e10-0410-8d5c-99ab1f9c6602
automatically purge archive temporary directory

git-svn-id: http://piwigo.org/pem_svn/trunk@377 d4d6b01b-5e10-0410-8d5c-99ab1f9c6602
safer test after git clone

git-svn-id: http://piwigo.org/pem_svn/trunk@378 d4d6b01b-5e10-0410-8d5c-99ab1f9c6602
ticket #22 : more relevant icon and sentences for SVN/Git

git-svn-id: http://piwigo.org/pem_svn/trunk@379 d4d6b01b-5e10-0410-8d5c-99ab1f9c6602
Merge remote-tracking branch 'remotes/git-svn'