Remove duplicate imports from xml modules.
Rewrite of rest dispatch generators.
All generators have been rewritten to allow external extensions.
Because of type-safety concerns, delegates code and generators have been removed and moved to an extension.

Summary of squashed commits:
splitted generator possible methods across different interfaces.
Generate stub rest resources.
Improve generated rest resources. Generate stub rest actions.
Carry end-point params from the method to the impl.
Re-implemented resource actions.
Adapted and reused existing serializer generators
Apply chain-of-command to select an action generator
Remove duplicated classes between old and new rebind
Re-implemented sub resources.
Added supporting code for resource generator extensions.
Reduce the number of invocations of the generator during compile
Introduced an abstraction for resource method generators
Introduced an abstraction for resource generators
Reuse abstract generator methods.
Removed old rest-dispatch generators
Velocity macros. Param. types support in class def
Removed client code for resource delegates
Update carstore references to res. delegates
ResourceMethod -> Method
Improved the indentation of template arguments
Use parameterized names when possible.
canGenerate() should not throw
Added proper equals to ClassDef
Ensure the printwriter is always closed.
Increase visibility of action generator methods
Update DispatchRest module DTD to 2.7
Register all generators through multibinder
Simplify code
Blacklist InterceptorMismatchException
Remove Guava usage from GWT code
Remove carstore
Warn if HEAD or GET has body or form params
Improved method generator restrictions
Merge pull request #622 from ArcBees/cv_rest_generators_v2_p1

Rewrite Rest-Dispatch generators to allow extensions