Adds supports for the majority of features2d to the Java wrappers:

* Adds the main features2d header to the parse list for the generator.
* Removes the manual definition of drawKeypoints and drawMatches since these are now included in the main header.
* Updates the generator to ignore SimpleBlobDetector, FlannBasedMatcher and DescriptorMatcher as these cause conflicts with the generator. This is okay since these were not previously included in the distribution anyway, so no harm is done.

modules/java/generator/gen_java.py

@@ -13,6 +13,8 @@ else:
 class_ignore_list = (
     #core
     "FileNode", "FileStorage", "KDTree", "KeyPoint", "DMatch",
+    #features2d
+    "SimpleBlobDetector", "FlannBasedMatcher", "DescriptorMatcher"
 )
 
 const_ignore_list = (