Add ability to keep LEDBlinky open upon exit

[jlvandusen]

Possible to add 1 more property that is named
LEDBlinkyCloseOnExit

it can be yes or no
If No it will then keep ledblinky open even after closing retrofe
this will correct issues with launching retrofe and launching another retrofe from it... when you close the 2nd instance, it closes ledblinky causing ledblinky to crash with error state

NOTE: Arzoo checks for new instances of ledblinky so leaving it resident will correct this.

[phulshof]

I've seen your pull request; I'll see if I can embed your changes in my code base in a few weeks.

[jlvandusen]

@phulshof - did you complete your changes?