project: Load README faster by fixing getReadmeFileName()

This reduce tps of the page from 3529ms to 38ms.
project: Load README faster by remove duplication.

Remove duplicated calling of project.readme in the view. This reduces
tps of the page from 38ms to 33ms.
Merge pull request #118 from npcode/fix/overview-slowness

Fix the slowness of the Project Overview page.