[OGRE-134] Make mAttributes member protected in UserObjectBindings

[paroj]

[reporter="vekoon", created="Sun, 27 Jan 2013 22:10:47 +0100"]

The mAttributes member variable is private at the moment.

Either exposing it or adding a getter for it under the protected methods would allow subclasses to iterate through the values, instead of forcefully accessing them by name.

[paroj]

[author="koenmertens", created="Thu, 13 Aug 2015 17:12:54 +0200"]

Created a pull request containing a fix [ https://bitbucket.org/sinbad/ogre/pull-requests/558/fixed-issue-134-make-mattributes-member/diff ]