Clean-up on isle five for __ast_request_and_dial() and ast_call_forward().

Clean-up on isle five for __ast_request_and_dial() and ast_call_forward().

* Add locking when a channel inherits variables and datastores in
__ast_request_and_dial() and ast_call_forward().  Note: The involved
channels are not active so there was minimal potential for problems.

* Remove calls to ast_set_callerid() in __ast_request_and_dial() and
ast_call_forward() because the set information is for the wrong direction.

* Don't use C++ keywords for variable names in ast_call_forward().

* Run the redirecting interception macro if defined when forwarding a call
in ast_call_forward().  Note: Currently will never execute because the
only callers that supply a calling channel supply a hungup or zombie
channel.

* Make feature_request_and_dial() put the transferee into autoservice when
it calls ast_call_forward() in case a redirection interception macro is
run.  Note: Currently will never happen because the caller channel (Party
B) is always hungup at this time.

* Make feature_request_and_dial() ignore the AST_CONTROL_PROCEEDING frame
to silence a log message.
........

Merged revisions 348464 from http://svn.asterisk.org/svn/asterisk/branches/1.8

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/10@348465 65c4cc65-6c06-0410-ace0-fbb531ad65f3