Add support for net46 target framework

[Zyano]

Types of Changes

Prerequisites

Please make sure you can check the following two boxes:

• [ X] I have read the CONTRIBUTING document
• [X ] My code follows the code style of this project

Contribution Type

What types of changes does your code introduce? Put an x in all the boxes that apply:

• Bug fix (non-breaking change which fixes an issue, please reference the issue id)
• [ X] New feature (non-breaking change which adds functionality, make sure to open an associated issue first)
• Breaking change (fix or feature that would cause existing functionality to change)
• My change requires a change to the documentation
• I have updated the documentation accordingly
• I have added tests to cover my changes
• All new and existing tests passed

Description

PR from discussion in #24

[claassistantio]

All committers have signed the CLA.

[FlorianRappl]

Thanks, a couple of things are missing though (I could also add them):

• CHANGELOG entry (for 0.14)
• Build system update (to also make / include the .NET 4.6 build)

[Zyano]

Hey, I hope the two commit that relate to changelog.md and build.cake are what you had in mind if not then it might be easier to modify them yourself :)

[FlorianRappl]

Hey, I hope the two commit that relate to changelog.md and build.cake are what you had in mind if not then it might be easier to modify them yourself :)

Looks awesome - much appreciated!