Update index.rst

Bug: Documentation had two instances of having duplicate words in two different places.

Proposed fix: removed the word "us" after 'community/contact'

Bug location (pic): http://openhatch.org/bugs/file639/Screen%20Shot%202014-01-05%20at%2010.43.49%20AM.png 
Bug report: http://openhatch.org/bugs/issue914