Black list of entities, that are not implemented in Java API added to javadoc generator

OpenCV namespace added;
Default values for camera_id added;
Aditional constructor with cameraId added.
Resolution added to FPS message.

FPS meter added;
Camera switching posibility added;
Attributes loading for layout filed implemented.

Memory leak in color-blob-detection sample fixed;
Default face size in face-detection is set to 20%;
Error handling improved;
Some possible mat leak fixed;
Manager verison and engine interface version incremented to fix incompatibilities;
Docs updated;

Some unification done to simplify camera switching.

Some code refactoring done.

Frame format setter added to both views.

The rst_parser.py was unintentionally corrupted by normalization.
This fix repairs the script and fixes Java API generation.

OpenCV info library name fixed;
Minimum API level for OpenCV library project increased up to 3 for using message dialogs.

Based on pull request #31 (thanks to Eric Christiansen)
Support for Java is turned off by default and can be enabled setting
BUILD_opencv_java to ON (e.g. cmake -DBUILD_opencv_java=ON ..)

Previously the generator always uses hardcoded list of modules.
This fix replaces hardcoded list with actual set of modules coming from cmake.