[#2] Wrote unit tests, and fixed logic

- Wrote unit tests to ensure that expected output is written, using test spies
  (see http://blog.lyte.id.au/2014/03/01/spying-with-phpunit/ for the approach).
- Modified `RouteCollection` to add a `getRoute()` method; simplifies logic
  required for displaying usage message for a single route. Returns `null` if
  route is unknown.
- Modified logic from PR to pull the `$name` only if no route was matched, and,
  if the `$name` matches a known route, will then call
    `showUsageMessageForRoute()` with the named route, returning a status of 1.
[#2] Detailed naming conventions

- Detailed that commands and route names should have a 1:1 relation in order to
  facilitate the help system.
Allow specifying filters/validators by name

- Allow passing filters and validators by name (instead of requiring instances).
- Allow passing callables for filters and validators; cast them to
  `Zend\Filter\Callback` and `Zend\Validator\Callback`, respectively.
Merge branch 'master' of git://github.com/zfcampus/zf-console into zfc6
Added useful console input parameter filters.
Implements #6.
Merge pull request #8 from slaff/zfc6

Supplied useful filters
[#8] CS fixes (control spacing)
[#8] Review and defensive coding

- Explode:
  - Most ZF2 filters allow either a scalar value, or an array of options
    to the constructor. Updated the constructor to allow an array of
    options.
- Json:
  - Do not use the scream operator; json_decode() doesn't raise warnings
    anyways. Instead, explicitly trigger an E_USER_WARNING if an error
    occurs, before returning the original value.
  - Also, json_decode() indicates that true, false, and null are all
    expected and possible values. Only in the case of null could an
    error occur; in that case, we determine whether or not to trigger a
    warning.
- QueryString:
  - Use the Json filter instead of json_decode() so that we get warnings
    for invalid data.
  - Applied code calisthenics to foreach loop to remove nesting.
[#8] Documented new filters
Merge branch 'hotfix/8'

Close #8