allow torrent.addPeer() call before swarm is created (before 'infohash' and 'listening' events)
allow torrent.addPeer() call before swarm is created (before 'infohash' and 'listening' events)

For #365

sideffect0/webtorrent,gillesdemey/webtorrent,ericwooley/webtorrent,Stiveknx/webtorrent,serafinfernandez/webtorrent,madmarks/webtorrent,sideffect0/webtorrent,gillesdemey/webtorrent,jamesliu96/webtorrent,Stiveknx/webtorrent,beni55/webtorrent,adriagalin/webtorrent,joshterrill/webtorrent,madmarks/webtorrent,arestov/webtorrent,dan-hill/webtorrent,jamesliu96/webtorrent,ngjermundshaug/webtorrent,fisch0920/webtorrent,nicola/webtorrent,lucamaraschi/webtorrent,LinusU/webtorrent,ngjermundshaug/webtorrent,karissa/webtorrent,yciabaud/webtorrent,MiracleBlue/webtorrent,FabianFrancoRoldan/webtorrent,MiracleBlue/webtorrent,karissa/webtorrent,loon3/webtorrent,whitef0x0/webtorrent,solderzzc/webtorrent,nicola/webtorrent,feross/webtorrent,akiva/webtorrent,rom1504/webtorrent,adriagalin/webtorrent,feross/webtorrent,fisch0920/webtorrent,yciabaud/webtorrent,webtorrent/webtorrent,serafinfernandez/webtorrent,ericwooley/webtorrent,beni55/webtorrent,rozifus/webtorrent,joshterrill/webtorrent,akiva/webtorrent,loon3/webtorrent,whitef0x0/webtorrent,solderzzc/webtorrent,dan-hill/webtorrent,webtorrent/webtorrent,LinusU/webtorrent,rozifus/webtorrent,FabianFrancoRoldan/webtorrent,lucamaraschi/webtorrent