Feature/validator context

Tested the code against the following script:

```php
<?php
use HylianShield\Validator\Context\Context;

$context = new Context();
$context->addAssertion('I am alive', true);

$context->addIntention('Register an intention');
$context->addAssertion(
    'Check if we have an intention',
    $context->getIntentions()
);

$context->addViolation(
    'Ran code in the bootstrap of our unit test suite',
    1,
    array(
        'file' => __FILE__,
        'line' => __LINE__
    )
);

var_dump($context->getAssertions());
var_dump($context->getIntentions());

$violations = $context->getViolations();

foreach ($violations as $violation) {
    var_dump(
        $violation->interpolate(
            'Something went wrong in {file}:{line}',
            '{',
            '}'
        ),
        $violation->interpolate(
            'Something went wrong in :file::line'
        )
    );
}

```

Resulted in:

```
array(2) {
  [0] =>
  class HylianShield\Validator\Context\Indication\Assertion#6 (2) {
    protected $result =>
    bool(true)
    protected $description =>
    string(10) "I am alive"
  }
  [2] =>
  class HylianShield\Validator\Context\Indication\Assertion#9 (2) {
    protected $result =>
    bool(true)
    protected $description =>
    string(29) "Check if we have an intention"
  }
}
array(1) {
  [1] =>
  class HylianShield\Validator\Context\Indication\Intention#8 (1) {
    protected $description =>
    string(21) "Register an intention"
  }
}
string(73) "Something went wrong in /home/johmanx/git/validator/test/bootstrap.php:33"
string(73) "Something went wrong in /home/johmanx/git/validator/test/bootstrap.php:33"
```