Add morphClass property to allow polymorphic relations on extended models
implement view name aliases
Merge pull request #4388 from alprs/view-name-alias

[4.2] Implement view name aliases
Code organization.
Merge pull request #4247 from deiucanta/4.1

Add morphClass property to allow polymorphic relations on extended models
Code organization.
Merge branch '4.1' into 4.2
Merge branch '4.2'