Fixes #5149 - Pulls widgets library into Elgg_WidgetsService
Refs #5149 - Removes obsolete private API documentation
Refs #5149 - Adds explicit methods visibility
Refs #5149 - Added ElggWidgetsServiceTest
Refs #5149 - Fixes tests bug
Refs #5149 - Adds getAllTypes and getNameByType methods, removes getWidgets
Refs #5149 - Replaces setValue with setFactory for services creation in Elgg_ServiceProvider
Fixes #5189: cache handler accepts view names with hyphens
Allow cache handler parseRequest to be tested, simplify validation logic
Fixes #5247 - Adds missing translation strings and fixes bad usage
Merge pull request #5193

Conflicts:
	engine/classes/Elgg/CacheHandler.php
	engine/classes/Elgg/EntityDirLocator.php
merge pull request #5160 and fixed coding standard issues

Conflicts:
	engine/classes/Elgg/ServiceProvider.php
moved widgets unit test
Merge pull request #5248 from Srokap/ticket_5247

Fixes #5247 - Adds missing translation strings and fixes bad usage
do not want to support elgg_echo('entity') - too developer focused - users should not know what an entity is
localized install exceptions