Fix coding guidelines incoherences. Code should match PSR1/2 now, and
php-cs is set to check it on each commit.
Also fixed the Git hook to take into account only added, modified,
copied and renamed files (preventing errors when trying to check deleted
files).
Closes#1260.
* Fix php-cs according to https://github.com/ampache/ampache/issues/1251
to fix travis build. Use composer to force the 1.* version to be used.
* Add `encoding` fixer.
* Use the same set of fixers in Git commit hook and test script.
* Update hooks and scripts.
* Fix a braces issue detected by php-cs.
Closes issue #1251.