DLP Powershell improvements

- Add Update-DlpGitProject to manage many DLP clients & their repos
- Add Decrypt-SecureString
- Improve Convert-OpenSSLPemToPfx
- Change the Invoke-GitCommandOnDlpRepositories function into
  Invoke-GitCommandOnMultipleRepositories
- Add Set-DLPProjectContext function, although it's almost already obsolete
Minor DLP SolutionScripts improvement
Powershell init: Detect Python, Vim, and AzureSDK directories
Various Powershell minor improvements

- Add vless function, a pager using vim
- Add Get,Set-Clipboard to interact with Windows clipboards
- Set aliases for .NET framework executables like aspnet_regiis etc
Powershell Chocolatey fixes & functions

- Look for choco in new default dir
- Better Get-WebPiPackages function
- Add Get-InstalledChocolateyPackages function
Change function names to not conflict w/ PSCX