Add bower and grunt in gitignore.

.gitignore

@@ -69,4 +69,20 @@ docs/_build/
 target/
 
 
+### grunt ###
+# Grunt usually compiles files inside this directory
+dist/
+
+# Grunt usually preprocesses files such as coffeescript, compass... inside the .tmp directory
+.tmp/
+
+
+### Bower ###
+bower_components
+.bower-cache
+.bower-registry
+.bower-tmp
+
+
+### Local files ###
 config.py