Disable race detector during tests due to memory usage

The tests are using way too much memory with the race detector enabled causing
the build machines to fall over. Cursory profiling shows no leaks but it may
need a closer look. For now, it will be disabled but this cannot be permanent.

circle.yml

@@ -21,8 +21,11 @@ test:
     - test -z $(gofmt -s -l . | tee /dev/stderr)
     - go vet ./...
     - test -z $(golint ./...          | tee /dev/stderr)
-    - go test -race -test.v ./...:
-        timeout: 600
+    - go test -test.v ./...
+
+    # Disabling the race detector due to massive memory usage.
+    # - go test -race -test.v ./...:
+    #     timeout: 600
 
     # TODO(stevvooe): The following is an attempt at using goveralls but it
     # just doesn't work. goveralls requires a single profile file to be