Add "root" to callergraph dot work.
Add "root" to callergraph dot work.

Use the string "root" for the target object of the generated callergraph
DOT pages. This will prevent the occurences where two things have the
same node name from colliding.

See LRBLA, where the option LRBLA calls the routine LRBLA, leading to an
incorrect graph.

Change-Id: Idd231d49a0f42932ce7d101a868eeeabd02ae6be

OSEHRA/VistA,OSEHRA/VistA,OSEHRA/VistA,OSEHRA/VistA,OSEHRA/VistA,OSEHRA/VistA