- Move two functions to static that wasn't for some reason

- Add doxygen comments
- Remove un-needed assignment at declaration of variable
- Formatting fixes (whitespace)
- Add optin_debug in front of complex debugging output
- Move forward declarations of functions to top of file
- Fix error message for bad allocation in sip registry 
(Note: Review to line 6050 in this too large file)


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@8750 65c4cc65-6c06-0410-ace0-fbb531ad65f3