add backlog of feature tests and refactor existing tests 

NOTES:

this commit includes tests for the features implemented on other branches and the functional changes in this PR are in common with those branches
* PR #140 - add project avatar image to Project index and show pages (merged into upstream master)
* PR #141 - add "sync pending" notice and more pretty urls (merged into this PR)
* PR #143 - fix inconsistent capitalization of signup/sign-in links (merged into upstream master)
* PR #172 - supress visibility of unclaimed tips (merged into upstream master)

many tests were refactored to use the uniform url scheme and to accomodate more test project instances and providers other than github


CHANGES:

* added cucumber test for project management ability of collaborators/non-collaborators
* added cucumber tests for searching and adding projects (PR #140)
  * add test for and searching/adding valid and invalid repos
  * test also for organization avatar image
  * added features/find_or_create_project.feature
  * added features/project_steps.rb
* added cucumber tests for "initial sync pending" notice (PR #141)
  * added features/manage_project.feature
* added cucumber tests for signup and sign-in links (PR  #143)
  * added features/signup_signin.feature
  * added features/step_definitions/home_steps.rb
* added rspec controller and routing tests for most actions of all controllers
  * added spec/controllers/tips_controller_spec.rb
  * added spec/controllers/withdrawals_controller_spec.rb
* factored out commonality from some existing steps (ie. "When I visit ...")
* deferred loading of collaborators and commits until project actually "syncs"
* handles up to three test @project instances
* merged latest upstream master and reconcile tests
* added catch-all route and tests
* merged in the latest project-management branch (PR #141)
* seperated concerns out of features/step_definitions/common.rb into
         features/step_definitions/project_steps.rb
         features/step_definitions/tips_steps.rb
         features/step_definitions/user_steps.rb
* merged features/step_definitions/web.rb into
         features/step_definitions/common.rb
* merged features/step_definitions/tip_modifier_interface.rb into
         features/step_definitions/tips_steps.rb
* merged latest project-management branch (PR #141)
* merged latest upstream master and resolved conflicts
* added more examples to spec/controllers/users_controller_spec.rb
* added more examples to spec/controllers/projects_controller_spec.rb
* added more scenarios to features/manage_project.feature
* added more scenarios to features/pretty_paths.feature
* added more scenarios to features/sign_up_sign_in.feature
* reconciled features/min_tip_amount.feature with new test schema
* added a few more examples to features/min_tip_amount.feature
* moved the "min tip amount" step into features/step_definitions/tips_steps.rb
* delete test values added to CONFIG hash after every scenario
* merged latest upstream master including project-avatar branch (PR #141)