Convert OC_Appconfig to object interface

Implemented unittest for OC\AppConfig
check for valid appinfo in installer
Style fixes
Enable appconfig asserts
Merge branch 'master' into convert-oc_appconfig
Move legacy file to correct location
Add a FileInfo class which holds all info of a file and return that from getFileInfo, getDirectoryContent and search
Extends phpdoc for \OCP\File\FileInfo
remove ArrayAccess, JsonSerializable from the public part of FileInfo
add Support for passing a FileInfo instance to View->putFileInfo
Merge branch 'master' into fileinfo
Don't use is_array on FileInfo
Dont use php5.4 only features
remove more is_array from encryption
Merge branch 'master' into fileinfo

Conflicts:
	tests/lib/files/cache/cache.php
undo 3rdparty change
undo 3rdparty change
Moved steps to reproduce to the top

This prevents people to put their steps into the "Expected" section.
It is better to first read the steps to find out how users reached the
issue, then see what was expected and actually happened.
Added explicit quota + encryption questions
Added boldening of entries for readability