Merge pull request #58 from marksteward/master

Only include subscribed member faces (fixes #56)
- Changed wording on signup form and non-member landing page to suggest the minimum membership is for students, retirees or low income members.
- Changed required average subscription to £15/month
- Added emergency name and number to Join form, Edit account form and admin view of member.ph
p. Fixed #47
- Fixed #59
- Added 'Has emergency contact' to profile.php
- Changed calendar wording of 'bi-weekly' events to 'fortnightly'
Merge branch 'master' of github.com:londonhackspace/hackspace-foundation-sites
Fixes #57 photo.php not caching. Also added instructions about mod_rewrite dependency in the readme.
Fixed bug in profile link for new members faces list
Building a set of statistics pages. Added retention and member interests
Interest statistics charts now actually make logical sense.
Statistics rewording
Added aerospace to 'Special interests'
Uppercase UID before inserting into DB