Fix a number of problems with ast_sched_report().

1) It had numerous coding guidelines violations with regards to formatting.

2) It allocated memory using ast_calloc() that was never freed.

3) It didn't check for failure from the allocation.

4) It used sprintf() and strcat() to build the result, doing zero checking to
   prevent writing past the end of the provided buffer.

The function also lacks API documentation, but that has not been addressed in
this commit.


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@175829 65c4cc65-6c06-0410-ace0-fbb531ad65f3