Squashed commit of the following:

commit 8a646eb34ce1cce95b06a6f20e23591efa810d35
Author: Bastiaan Bakker <bbakker@xebia.com>
Date:   Wed Oct 16 23:42:59 2013 +0200

    skip all checking if Enforcement level is NONE.
    refactored variable names.

commit a57ea4200abccd466034e42438ba84aadcce898b
Author: Bastiaan Bakker <bbakker@xebia.com>
Date:   Wed Oct 16 22:56:50 2013 +0200

    renamed enum values for better consistency.

commit bfa9170647b80e2a0bce2076cce0e34f8db270c0
Author: Bastiaan Bakker <bbakker@xebia.com>
Date:   Thu Oct 10 22:21:16 2013 +0200

    renamed properties to requiredInstancesPerEnvironment and requiredInstancesEnforcement.

commit 3cfcf0bf9c2412877c80ac4070ea2a60bfac9a3f
Author: Bastiaan Bakker <bbakker@xebia.com>
Date:   Thu Oct 10 21:45:11 2013 +0200

    fix package names in xml
    reformat with XebiaLabs formatter.

commit 159ea09172741f42c7ae3794f73d46617ac51bcf
Author: Bastiaan Bakker <bbakker@xebia.com>
Date:   Tue Oct 8 14:47:48 2013 +0200

    renamed package

commit 7196bf49d5fdf8ece29979ab21311e0094f33312
Author: Bastiaan Bakker <bbakker@xebia.com>
Date:   Tue Oct 8 14:44:38 2013 +0200

    refactored based on feedback from @demobox: project name, property names, enum names, default enforcement level.

commit 91e13f1cb7fda67e9981ac7c2361ce202633e2d8
Author: Bastiaan Bakker <bbakker@xebia.com>
Date:   Tue Oct 8 11:42:28 2013 +0200

    renamed deployment-complete-validator-plugin to deployable-mapping-verifier-plugin.

commit 47cfaac9b094563c73916bf84ed11948d048bdfe
Author: Bastiaan Bakker <bbakker@xebia.com>
Date:   Thu Oct 3 16:32:55 2013 +0200

    Added invocation via a PostPlanProcessor instead of custom validator,
    because Deployit calls the custom validator before adding the Deployeds
    to the DeployedApplication.

commit ad0a0f2a9a6f3e8c2a6631b302981b1e8c023bf7
Author: Bastiaan Bakker <bbakker@xebia.com>
Date:   Thu Oct 3 14:43:42 2013 +0200

    added properties 'requiredDeploymentCardinality',
    'ignoreRedundancyRequirements' and 'ignoreCardinalityRequirements' to
    allow tuning of cadinality requirements.

commit fbbb3ab6d32c8af51afc58200f1cad80bc642794
Author: Bastiaan Bakker <bbakker@xebia.com>
Date:   Thu Oct 3 10:21:17 2013 +0200

    resolve / suppress raw types warning

commit b75513adee8a06f7d2cc5171dcda0655413f14e7
Author: Bastiaan Bakker <bbakker@xebia.com>
Date:   Thu Oct 3 09:47:38 2013 +0200

    first version. treats all Deployables as mandatory.