Is it possible to enable Location Services via Shell? Is it possible to enable Location Services(GPS or Google NetworkLocation) via ADB or Terminal Emulator?
I'm on a rooted Phone.

Extra Points: Is it also possible to change other system-related settings?
For Android 6.0 

To Enable use :

For GPS : adb shell settings put secure location_providers_allowed +gps

For Network : adb shell settings put secure location_providers_allowed +network

To Disable : 

GPS : adb shell settings put secure location_providers_allowed -gps

For Network : adb shell settings put secure location_providers_allowed -network