confbridge: Add flags column to CLI "confbridge list <conference>"

* Added the following flags to the CLI "confbridge list <conference>" output:
A - The user is an admin
M - The user is a marked user
W - The user must wait for a marked user to join
E - The user will be kicked after the last marked user leaves the conference
w - The user is waiting for a marked user to join

* Added the following header to the AMI ConfbridgeList events:
WaitMarked, EndMarked, and Waiting.

(closes issue AST-1101)
Reported by: John Bigelow
Patches:
      confbridge-show-admin3.txt (license #5091) patch uploaded by John Bigelow
      Modified


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@381644 65c4cc65-6c06-0410-ace0-fbb531ad65f3