Missing database entries causes script to crash

[MajesticFalcon]

Describe the bug
The script relies on the user to edit it to match their environment. If the user does not have all the requirements perfectly entered, the script will crash.

To Reproduce
Steps to reproduce the behavior:

1. Fail to configure any of the following variables: Device Type, Site, Role, Vlan
2. Go to scripts
3. Click on the main script
4. See error

Expected behavior
Provide the user with why the script is failing in a more elegant and easy to understand way.

Screenshots
If applicable, add screenshots to help explain your problem.

Desktop (please complete the following information):

• OS: Win10
• Browser: Chrome