Blender Git Loki

Refactor Collada: Moved Classes into separate files

Renamed AnimationCurveCache to BCAnimationCurveContainer
because this is really not a cache but just a set of Data that
prepares the export of FCurves. This container only lives during
export and is otherwiose not used for anything else.

The BCAnimationCurveContainer is not depending on Collada in any way.
Theoretically it could be used also from Python, but this is another story.

Additions in more detail:

Classes:

* BCAnimationCurve
a wrapper for handling FCurves tied to an object within the
Animation Exporter

* BCAnimationCurveContainer
A container to keep all FCurves in one place. It also maintains
creation and deletion of temporary FCurves needed to export data
without interfering with the User's production data in Blender.

* BCMatrix
Handy class for making float mat[4][4] a primetime resident in
the code. Not necessary but nice.

Support functions:

* bc_get_children(std::vector<Object *> &child_set, Object *ob, Scene *scene)
returns the immediate children of an object into a set

* bc_string_after(const std::string& s, const char c)
returns the string after the last occurance of char

* bc_startswith(std::string const & value, std::string const & starting)
returns true if the string starts with the starting sequence

* bc_endswith(std::string const & value, std::string const & ending)
returns true if the string ends with the ending sequence