Fix function documentation for PostDirectMessage
Update GetFollowerIDs with total_count to limit API calls

Updated GetFollowerIDs() with a total_count parameter which will limit
the total amount of retrieved FollowerIDs to avoid getting rate limited
by twitter. Also made it clear in the parameter documentation that
setting 'count' to a small value might get you rate limited rather
quickly.
remove GetFriendsTimeline from doc
Merge pull request #70 from Xsns/master

Remove "GetFriendsTimeline"