fixes of obvious code mistakes

[DamirAinullin]

Some fixes of obvious code mistakes or warnings

[azurecla]

Hi @DamirAinullin, I'm your friendly neighborhood Azure Pull Request Bot (You can call me AZPRBOT). Thanks for your contribution!

In order for us to evaluate and accept your PR, we ask that you sign a contribution license agreement. It's all electronic and will take just minutes. I promise there's no faxing. https://cla.azure.com.

TTYL, AZPRBOT;

[azuresdkci]

Can one of the admins verify this patch?

[hovsepm]

@azuresdkci test this please

[hovsepm]

@DamirAinullin Thank you for the contribution. Please sign the CLA so we can take in your contribution.

[azurecla]

@DamirAinullin, Thanks for signing the contribution license agreement so quickly! Actual humans will now validate the agreement and then evaluate the PR.

Thanks, AZPRBOT;

[DamirAinullin]

@hovsepm, Done.

[markcowl]

@DamirAinullin This is awesome, thank you! Since we are now throwing some (obviously intended but not thrown before) exceptions, I will execute a complete test run before merging.

on demand run here: http://azuresdkci.cloudapp.net/view/1-AzurePowerShell/job/powershell-demand/911/