[ENHANCEMENT] Adding Proposal for Swift Project and Files.

[rweindl]

@pkluz @chhaylatte @allewun Adding a first Proposal for the OriginateTheme Swift Project. This PR includes all necessary files required for allowing the same functionality as the ObjectiveC library. I included a secondary target in the same project which adds all Swift functionality. Please checkout the source and take a look on it.

The goal is that in future when installing the pod the user can specify with a flag 'swift3.0' or 'objc' for which language the Code Generation should take place. Later the framework uses the ObjectiveC or Swift target for the target code base.

As soon this first pass of the PR gets reviewed and discussed the same PR should be used for adding the Swift Code generation phase.

Also added in the Colors and Fonts Model an example for the generated file. Later only very few code needs to be added to the Colors, Components, Fonts Code Generation to reflect same functionality as we have for Objective-C.

Thanks for taking a look on it!

PS: Also added a Playground in the following which I used to test functionalities while development. Maybe its also helpful for you all: OriginateTheme.playground.zip

Screenshot:

[pkluz]

Side Note: Let's have this PR point to a new branch called swift-3