Changes to views, tests, settings and api

- HTML views: multiple fixes for display and layout problems
- HTML views: removed debugging text from navbar
- HTML views: projects descriptions on index page are now truncated
- HTML views: fixed some typos
- tests: acceptance_spec_helper improvements
- tests: fixed some factories
- tests: fixed transaction issue
- rails: specified Utime zone UTC explicitly
- rails: added rescue_from for ActiveRecord::RecordNotUnique. closes #13
- rails: changed error pages to not display error messages (security
issue).
- rails: dataset json file generation seems to be working
- rails: moved admin used from migrations to seeds with harvester and
added settings for email and password
- rails: added will_paginate gem for paging audio recordings will
datasets are not ready to be used
- rails: removed mysql gem