Replace text on home page with pitch placeholders
Merge pull request #48 from okfn/10-second-pitch

Replace text on home page with pitch placeholders
templates: Load cms tags

This allows us to use placeholder tag
Add board and advisory-board pages

Hardcodes the urls for the two boards and units
Update tests to revers to units instead of unit-lists
Tests added for board and advisory board
Remove email from board member listing

We should not make emails of board members available to visitors (but emails of
unit members are still available since that's "our" staff's work emails)