remove deprecated functions from choco templates

[Jon]

The chocolateyinstall.ps1.erb and chocolateyuninstall.ps1.erb templates use deprecated Write-ChocolateySuccess and Write-ChocolateyFailure functions.

Figure out what uru needs (likely a simple try/catch, a Write-Host, and a throw $_.Exception) and implement.

[Jon]

Remove deprecated Chocolatey functions. Closes #79

→ <<cset 5d6d269d035f>>