Prepare project for import into bazelbuild/continuous-integration.

This commit changes the imports to point at the original CI repository, updates the Go modules file to include the metrics project and removes all dependencies from the documentation.
The use of Go modules makes these dependencies obsolete.
diff --git a/metrics/main.go b/metrics/main.go
index 97217eb..35a3104 100644
--- a/metrics/main.go
+++ b/metrics/main.go
@@ -8,10 +8,10 @@
 	"os"
 	"time"
 
-	"github.com/fweikert/continuous-integration/metrics/clients"
-	"github.com/fweikert/continuous-integration/metrics/metrics"
-	"github.com/fweikert/continuous-integration/metrics/publishers"
-	"github.com/fweikert/continuous-integration/metrics/service"
+	"github.com/bazelbuild/continuous-integration/metrics/clients"
+	"github.com/bazelbuild/continuous-integration/metrics/metrics"
+	"github.com/bazelbuild/continuous-integration/metrics/publishers"
+	"github.com/bazelbuild/continuous-integration/metrics/service"
 )
 
 var (