Be less picky with guessTooltip()

e.g. show tooltip for Python classes like

    from django.http import HttpResponse

    HttpResponse(

package.json

@@ -55,7 +55,7 @@
         "c9"
     ],
     "c9plugins": {
-        "c9.ide.language": "#8d56ee72c5",
+        "c9.ide.language": "#e2fab5d5fa",
         "c9.ide.language.css": "#36150db526",
         "c9.ide.language.generic": "#365368d108",
         "c9.ide.language.html": "#e7b5ab7ff8",