Add apache::mod::uwsgi

Needed for Graphite and Gdash. I don't like the style of the Apache module, but
it is what it is, so I am reproducing its coding conventions.

Change-Id: I6322f4bdca70cc3acda49b7dacfc7971fa306ee4
Configure Gdash and Graphite to use mod_uwsgi

Use apache::mod::uwsgi added in I6322f4bdc.

Change-Id: I4d1a9dfe9a45648feee39279f33f8afcd24fe13e