Replace highline dependency with standard Ruby

There are two minor differences from the `highline` version.

* Character echoing on password input has been disabled altogether.

  This is due to limitations of the `console/io` library.

* The password length validation has been removed.

  There's no feature like this in the `console/io` library and there's no
  validation like this on the model. Instead of reimplementing it, I think we
  might as well remove it.

The test for `ChangePassword` could use some improvement, especially to avoid
stubbing a method on the object under test.

The change to `ChangeUserPassword` is tangential, but fixes a bug where the
password wouldn't be updated due to a failing validation (`password` and
`password_confirmation` don't match).
Merge pull request #340 from Koronen/remove-highline-dependency

Replace highline dependency with standard Ruby
Update OpenShift Docs for Ruby 2.0 Cartridge

Update the instructions for OpenShift for the newly added Ruby 2.0
Cartridge. Due to an older version of Bundler, some workarounds have
to be included.
Set SECRET_TOKEN as OpenShift Environment Variable

This sets the SECRET_TOKEN variable as OpenShift Environment Variable,
rather than committing the SECRET_TOKEN to the repo.

[skip ci]
Merge pull request #342 from jasonngpt/updateOpenShiftDocs

Update OpenShift Docs for Ruby 2.0 Cartridge
Fix FeverAPI test flakiness

Attempts to address #331, mainly by stubbing `Time.now`.

* Adds whitespace, splitting tests into setup, execution and verification steps.

* Fixes a typo (`standart` -> `standard`).

* Introduces `last_response_as_object` helper.

  This allows splitting the assertions into two parts, one asserting inclusion
  of standard keys and one asserting inclusion of keys specific to each action.

* Stubs `Time.now`, splits assertions and makes use of the includes matcher.
Merge pull request #341 from Koronen/fix-api-test-flakiness

Fix FeverAPI test flakiness
Bump `backports`, `multi_json` and `sinatra`

This is the result of running `bundle update sinatra-contrib` and fixes the
following error when deploying to Heroku.

> Could not detect rake tasks
> ensure you can run `$ bundle exec rake -P` against your app with no environment variables present
> and using the production group of your Gemfile.
> This may be intentional, if you expected rake tasks to be run
> cancel the build (CTRL+C) and fix the error then commit the fix:
> rake aborted!
> Bad file descriptor - bundle/ruby/2.0.0/gems/backports-3.3.5/lib/backports/1.9.1/io/open.rb
> bundle/ruby/2.0.0/gems/backports-3.3.5/lib/backports/1.9.1/io/open.rb:2:in `close'
> bundle/ruby/2.0.0/gems/backports-3.3.5/lib/backports/1.9.1/io/open.rb:2:in `open'
> bundle/ruby/2.0.0/gems/backports-3.3.5/lib/backports/1.9.1/io/open.rb:2:in `<top (required)>'
> bundle/ruby/2.0.0/gems/backports-3.3.5/lib/backports/tools.rb:328:in `require'
> bundle/ruby/2.0.0/gems/backports-3.3.5/lib/backports/tools.rb:328:in `require_with_backports'
> ...

See <https://gist.github.com/Koronen/4f95da9262f99612ed44> for the full stack
trace.

Fixes #343.
Merge pull request #344 from Koronen/bundle-update-sinatra-contrib

Bump `backports`, `multi_json` and `sinatra`
default sort order to asc