Remove coveralls. It doesn't work with gb

.travis.yml

@@ -5,11 +5,9 @@ install:
  - go get github.com/constabulary/gb/...
  - go get github.com/golang/lint/golint
  - go get github.com/fzipp/gocyclo
- - go get github.com/mattn/goveralls
 
 script:
  - gb build github.com/matrix-org/dendrite/roomserver/roomserver && ./hooks/pre-commit
- - $HOME/gopath/bin/goveralls -service=travis-ci
 
 notifications:
     webhooks:

README.md

-# Dendrite [![Build Status](https://travis-ci.org/matrix-org/dendrite.svg?branch=master)](https://travis-ci.org/matrix-org/dendrite) [![Coverage Status](https://coveralls.io/repos/github/matrix-org/dendrite/badge.svg?branch=master)](https://coveralls.io/github/matrix-org/dendrite?branch=master)
+# Dendrite [![Build Status](https://travis-ci.org/matrix-org/dendrite.svg?branch=master)](https://travis-ci.org/matrix-org/dendrite)
 
 Dendrite will be a matrix homeserver written in go.