BGE: added bge.logic.{get,set}AnimRecordFrame functions

BGE: added bge.logic.{get,set}AnimRecordFrame functions

By using getAnimRecordFrame(), game developers have access to the frame
number used by the "Record animation" feature. This enables them to
record additional information in Blender's F-Curves and ensuring perfect
synchronization with the information already recorded by Blender.

The setAnimRecordFrame() can be used to change the frame number at which
animations are recorded, for example to introduce delays the recording that
do not require delays in the actual game/simulation run.

The getter/setter functions in KX_KetsjiEngine are not directly named after
property they access (m_currentFrame). I found "current frame" to be too
vague for a public interface, hence chose a more descriptive name.

Reviewers: moguri, hg1, campbellbarton, panzergame, aligorith

Reviewed By: panzergame, aligorith

Differential Revision: https://developer.blender.org/D1449