Include deletion of switch when delete environment called

[chrissound]

This should fix #108. I have tested it by doing bgctl switch create test123 and bgctl switch delete test123 which behaved correctly.

[HarrisKirk]

The full test is: bgdctl deploy testsite (lke, nodebalancer and switch are all created) bgdctl rm testsite (all 3 are deleted)

I tried the above and the test was a success