Generate Invoke-Build Tasks from Psake Tasks

[JustinGrote]

Description

This provides a heavily improved version of the Invoke-Build Psake convert script, and uses it to generate the invoke-build from the psake tasks.

Motivation and Context

Currently IB and psake tasks are manually kept in sync, which may lead to problems if they are not tested together.

How Has This Been Tested?

Pester tests included

Screenshots (if appropriate):

Types of changes

• [ ] Bug fix (non-breaking change which fixes an issue)
• [X] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• [X] My code follows the code style of this project.
• [ ] My change requires a change to the documentation.
• [ ] I have updated the documentation accordingly.
• [x] I have read the CONTRIBUTING document.
• [X] I have added tests to cover my changes.
• [X] All new and existing tests passed.

[JustinGrote]

Should be ready for review now, darn Appveyor weirdness...

[devblackops]

Thanks @JustinGrote. I'll take a look at this over the weekend.