Hygiene: Various small cleanups

* Add some missing properties to Pager
* Remove unused Pager::getDefaultDirection and Pager::{g,s}etDefaultLimit methods
* Correct the return phpdoc on Index::getSort to match implementation
* Fix incorrect or partial docblock in many classes
* Remove unused class alias's in a few files
* Add missing class alias's in a few files
* Other minor cleanups from scripts/analyze-phpstorm.sh

Change-Id: I54a813b9ad1a0a5c9aa1abfb527184d9745b4794