First round of new classes to support PowerShell API

This was created by @alesliehughes as b71ac1cab4133c5aff022cd846e80809e8823868, and merged by @jaybazuzi.
Add InitialSessionState.Providers support
Implement SessionStateCommandEntry.CommandType
Add missing classes SessionStateApplicationEntry, SessionStateScriptEntry
Implement SessionStateCmdletEntry

Created by @alesliehughes as 41fa81278b0eac15547345bc0110ad27f23d467a.
Implement SessionStateFunctionEntry
Add some default sessionState Commands
Added Default State Aliases
Sync with Launchpad

Igor made the original release of Pash in spring of 2008. That
summer, Jonathan Ben-Joseph did some work on Pash as part of the Mono
Summer of Code. This merges in his changes.

Jonathan's release of his code on Launchpad indicated an MIT License. I
have email from Jonathan on 31 December 2012 agreeing to release that code
under BSD+GPL as well, so it aligns with Igor's original license.

@alesliehughes did the work of merging this code.
Correct build issues
Fix Console
Add @alesliehughes to AUTHORS.md
Merge pull request #67 from JayBazuzi/Merge-alesliehughes2

Merge @alesliehughes' changes from his fork of the original Pash.