Added more tests.

New tests are for loot_load_lists, loot_eval_lists and
loot_update_masterlist.
Fixed git_error not having an API error code.
Fixed bad permissions on LOOT .git folders.

They were being fixed when LOOT needed to delete them, but left with too
restrictive permissions otherwise. Now the permissions are write access
for all on successful operations too.
Fixed API loot_load_lists bugs.

The userlist path was being ignored, and the masterlist loaded again as
the userlist. The function now errors if either of the given paths does
not exist.
Fixed loot_eval_lists allowing invalid languages.