Add support to set the maximum number of files open when Asterisk loads using...

Add support to set the maximum number of files open when Asterisk loads using the 'maxfiles' configuration option. (issue #7499 reported by rkarlsba)


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@47933 65c4cc65-6c06-0410-ace0-fbb531ad65f3