Merge pull request #196 from franckstauffer/dev

[FIX] URL manager absolute URL generation
Begin implemetation
Add php traits
Merge pull request #197 from inthause/traits

Add php traits in \Change\Documents namespace
Improve memory management on documents
Add properties names on PropertiesValidationException message
Add properties names on PropertiesValidationException message
Fix Http/Rest actions
Add 'return $this' on document properties setter
Merge pull request #198 from inthause/traits

Add 'return $this' on document properties setter
Add 'Change-Memory-Usage' Response Header on Http\Rest Request
Merge pull request #199 from inthause/traits

Add 'Change-Memory-Usage' Response Header on Http\Rest Request
Add 'Change-Memory-Usage' Response Header on Http\Rest Request
Merge pull request #200 from inthause/traits

Add 'Change-Memory-Usage' Response Header on Http\Rest Request
FIX #195
Merge pull request #201 from inthause/traits

FIX #195
Add \Change\Db\Query\Expressions\Func specific sql generation
Improve memory management on Tree

Implementation of TreeManager::moveNode
Merge pull request #202 from inthause/traits

Improve memory management on Tree
Add saveVolatile property on Rbs_Workflow_Workflow document