Overlay: Public before private scope, public use function before Impl. class.
fx11 build project file: Remove unused lib path setting
Overlay: Fix function comment wording.
Overlay: Add missing return value (success) check.
Overlay: Fix error text wording.
fx11-build.pro: Error text like in our other dependency build projects
Overlay: Add sanity check in DEBUG compilations.
Overlay: Add Nullchecks before dereferencing.

* These variables are NULL if init() is not called, which is a possibility
code-path-wise.
Overlay: Code improvements

* Use ARRAY_NUM_ELEMENTS
Code style

* Remove this-> pointers on dereferencing
Overlay: Add return value checks.

* Add checks return value checks like we added in the fix fb5611 to
d3d10.cpp to d3d11.cpp.
* Instead of uninitialized variable, pass NULL OMSetBlendState which makes
it use a defined default.
Overlay: Add code comment on present logic
Overlay: Code improvement: Use map iterators
Overlay: Fix debug text. Use adequate type.

* The debug text was printing unsigned values as signed.
* Use ULONGs for all the refcount variables here; drops the need for a
static cast.
Overlay: Add code comment
Overlay: Remove unused return type.
Overlay: Code commenting: Add reference resource
Overlay: Add code comment

* Document expected case of deferred context creation failure
Overlay: Remove unused variable dwMyThread

* Only set, never read for d3d10 and d3d11.
Overlay: Correctly release/free D11State data

* Remove unnecessary method.
* Free D11StateBlock object
* Release pointer references on D11StateBlock membervariables