Explained how to create service principal (#3530)
Explained how to create service principal (#3530)

* Explained how to create service principal

Also made several other minor formatting edits

* Fixed formatting around Service Principal conn str

* Updated Nuget instructions

rohmano/azure-powershell,hungmai-msft/azure-powershell,ClogenyTechnologies/azure-powershell,rohmano/azure-powershell,AzureAutomationTeam/azure-powershell,rohmano/azure-powershell,krkhan/azure-powershell,zhencui/azure-powershell,rohmano/azure-powershell,atpham256/azure-powershell,devigned/azure-powershell,krkhan/azure-powershell,zhencui/azure-powershell,rohmano/azure-powershell,pankajsn/azure-powershell,naveedaz/azure-powershell,naveedaz/azure-powershell,pankajsn/azure-powershell,krkhan/azure-powershell,AzureRT/azure-powershell,pankajsn/azure-powershell,pankajsn/azure-powershell,naveedaz/azure-powershell,devigned/azure-powershell,krkhan/azure-powershell,pankajsn/azure-powershell,devigned/azure-powershell,zhencui/azure-powershell,AzureAutomationTeam/azure-powershell,AzureAutomationTeam/azure-powershell,atpham256/azure-powershell,hungmai-msft/azure-powershell,ClogenyTechnologies/azure-powershell,atpham256/azure-powershell,naveedaz/azure-powershell,hungmai-msft/azure-powershell,AzureRT/azure-powershell,ClogenyTechnologies/azure-powershell,krkhan/azure-powershell,zhencui/azure-powershell,rohmano/azure-powershell,devigned/azure-powershell,AzureRT/azure-powershell,AzureRT/azure-powershell,krkhan/azure-powershell,AzureAutomationTeam/azure-powershell,AzureAutomationTeam/azure-powershell,ClogenyTechnologies/azure-powershell,naveedaz/azure-powershell,AzureAutomationTeam/azure-powershell,naveedaz/azure-powershell,AzureRT/azure-powershell,devigned/azure-powershell,hungmai-msft/azure-powershell,atpham256/azure-powershell,pankajsn/azure-powershell,zhencui/azure-powershell,hungmai-msft/azure-powershell,zhencui/azure-powershell,atpham256/azure-powershell,atpham256/azure-powershell,AzureRT/azure-powershell,devigned/azure-powershell,ClogenyTechnologies/azure-powershell,hungmai-msft/azure-powershell