Minor fixes in startup script

[anblanco]

We were looking to integrate this code, and identified some fixes to the startup script we wanted to merge back upstream.

1. In batch %ERRORLEVEL% is mutated on every read, so we replace the exit with EXIT /B %ERRORLEVEL% to return 0 or 1 based on powershell error

   • Correction - the error level was captured in the closure of the IF block, which would always evaluate to 0 since the powershell had not yet had a chance to run. Two options to fix would be
     1. Enable Delayed Expansion and replace %ERRORLEVEL% with !ERRORLEVEL!
     2. Simply move the exit to the bottom of the script.

In our case, we opted for the latter because that made the script easier to read

2. Shutdown was not getting called because of Write-Host. Removed the Write-host block so that shutdowns can occur as expected.

[NoamDishon]

thanks anblanco. I came across the same issues and spent valuable time on this.... can someone merge this?