DOC: Modify ShapeLabelObject comments.

Author: bilgincc@gmail.com
Elongation is defined as
l_n \ l_{n-1} where l_n >= l_{n-1} >= .. l_1 are the principal moments

Change-Id: I05cf29a65db10edcc3a87b540e8f7bba8e3bf3f6
Merge topic 'EditDoxygen_ShapeLabelObject_1377283410'

b7d837d DOC: Modify ShapeLabelObject comments.