Commit of supervisor_child_count_only

[Jay Nelson]

Committed the addition of supervisor:count_children/1 to determine  
how many and what types of children a supervisor has without  
generating the list that which_children/1 returns.  Includes  
documentation update and test suite additions.  Also cleaned up  
warnings from list/1 guard by changing to is_list/1 guard in  
supervisor_SUITE.erl.

git fetch git://github.com/jaynel/otp.git supervisor_child_count_only

How do I test that the .xml changes build the documentation properly?

jay