Rename webtorrent source files

diff --git a/webtorrent/tracker_client.go b/webtorrent/tracker-client.go
similarity index 100%
rename from webtorrent/tracker_client.go
rename to webtorrent/tracker-client.go

diff --git a/webtorrent/tracker_protocol.go b/webtorrent/tracker-protocol.go
similarity index 100%
rename from webtorrent/tracker_protocol.go
rename to webtorrent/tracker-protocol.go