(GH-3) Added parsing of psake tasks

[gep13]

Description

Added the ability to parse the psakefile.ps1 file, looking for Task definitions. These are then provided for selection, and can be executed via the Integrated Terminal window.

Related Issue

#3

Motivation and Context

Allows the end user to easily "see" the build Tasks that they have available for their current project.

How Has This Been Tested?

Developer tests on my machine, needs much more testing, and comments.

Screenshots (if appropriate):

See related issue

Types of changes

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

Checklist:

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

[rkeithhill]

I wonder if we could add a command to psake that could use the PowerShell parser/ast to return the tasks rather than rely on regex's? We could have that command return JSON so it is more easily consumable from the extension.

[rkeithhill]

And there is already a command for that - Get-PSakeScriptTasks. Could call that and pipe to ConvertTo-Json to get output in JSON.

[gep13]

@rkeithhill that is an interesting idea :-)