Update TravisCI for Go 1.4 release.

Now that Go 1.4 has been released, this commit reverts the recent changes
which dealt with allowing TravisCI to work with go tip in between the Go
1.3 and Go 1.4 release cycle and updates the .travis.yml to invoke test
coverage tool from the new path in Go 1.4.

.travis.yml

@@ -4,7 +4,7 @@ go:
   - tip
 install:
   - go get -d -t -v ./...
-  - ./get_ci_cover.sh
+  - go get -v golang.org/x/tools/cmd/cover
 script:
   - go test -v -covermode=count -coverprofile=profile.cov
 after_success:

get_ci_cover.sh

@@ -1,8 +0,0 @@
-#!/usr/bin/env sh
-
-set -x
-if [ "$TRAVIS_GO_VERSION" = "tip" ]; then
-	go get -v golang.org/x/tools/cmd/cover
-else
-	go get -v code.google.com/p/go.tools/cmd/cover
-fi