* Break long lines

* Break long lines
* For readability, rewrote ResourceLoaderFileModule::readScriptFiles() to use a loop instead of an excessively cute nested array_map() construction.
* In ResourceLoaderFileModule, check file_get_contents() result for errors. Golden rule of error checking: always check fopen(). Every call to fopen will fail some day for some user.
* In mediaWiki.loader.filter(): broke up a complex multi-line conditional into multiple commented if statements, for readability.
* Possessive "its" has no apostrophe.