Rename TClassAttributeMap -> TDictAttributeMap

ROOT6 had TClassAttributeMap renamed to TDictAttributeMap starting
Wed Jan 22 15:31:23 2014 +0100.

Commit in ROOT6: e8ef04b45b8c81af508d736f61fe165435abfc35

Signed-off-by: David Abdurachmanov <David.Abdurachmanov@cern.ch>
Merge pull request #2227 from davidlt/root6-rename-TClassAttributeMap-to-TDictAttributeMap

Rename TClassAttributeMap -> TDictAttributeMap