Update api.rst
Update api.rst

Added missing since_id parameter for search()
atomicjets/tweepy,aganzha/tweepy,vishnugonela/tweepy,cogniteev/tweepy,yared-bezum/tweepy,kcompher/tweepy,sa8/tweepy,bconnelly/tweepy,kskk02/tweepy,obskyr/tweepy,raymondethan/tweepy,elijah513/tweepy,hackebrot/tweepy,techieshark/tweepy,rudraksh125/tweepy,truekonrads/tweepy,edsu/tweepy,zhenv5/tweepy,takeshineshiro/tweepy,robbiewoods05/tweepy,vikasgorur/tweepy,sidewire/tweepy,svven/tweepy,iamjakob/tweepy,wjt/tweepy,tuxos/tweepy,kylemanna/tweepy,damchilly/tweepy,srimanthd/tweepy,vivek8943/tweepy,Choko256/tweepy,thelostscientist/tweepy,awangga/tweepy,tsablic/tweepy,conversocial/tweepy,tweepy/tweepy,aleczadikian/tweepy,arunxarun/tweepy,IsaacHaze/tweepy,LikeABird/tweepy