Fix errors in comparing versions (admin area)

Signed-off-by: emanuele <emanuele45@gmail.com>
Skip . and .. directories when finding language files for version comparison

Signed-off-by: emanuele <emanuele45@gmail.com>
And separate better the different languages

Signed-off-by: emanuele <emanuele45@gmail.com>
And set the latest version as well (probably some js is now redundant)

Signed-off-by: emanuele <emanuele45@gmail.com>
Fixes for language strings

Signed-off-by: emanuele <emanuele45@gmail.com>
Merge pull request #1624 from emanuele45/versionerr

Errors in the compare versions page