.travis.yml: base for go with coveralls

.travis.yml

language: go
go:
  - tip
before_install:
  - go get github.com/axw/gocov/gocov
  - go get github.com/mattn/goveralls
  - go get github.com/bradfitz/goimports
  - go get github.com/golang/lint/golint
  - go get golang.org/x/tools/cmd/vet
  - if ! go get code.google.com/p/go.tools/cmd/cover; then go get golang.org/x/tools/cmd/cover; fi
  - git clone https://gist.github.com/0f22736320abe6be71ce.git $HOME/goclean
  - sudo apt-get update -qq
  - sudo apt-get install -y libxml2-dev
script:
  - $HOME/goclean/goclean.sh
  - $HOME/gopath/bin/goveralls -coverprofile=profile.cov -service=travis-ci