Changed googlecharts submodule url to use https.

.gitmodules

@@ -3,4 +3,4 @@
 	url = https://github.com/amber-smalltalk/amber
 [submodule "googlecharts"]
 	path = googlecharts
-	url = http://github.com/tomrake/googlecharts.git
+	url = https://github.com/tomrake/googlecharts.git