hard coding command-line executions into slave code
successfully kill browser, but browser does not close fast enough. conflicts with opening new URL
sleep code for one second so that browser can close properly before reopening
functioning code for OS X
Linux case
refactor setOS function
Linux switch case for killing browser
fixed formatting
exit the program when encoutering a fatal error
set the DISPLAY environment variable
string formatting
Merge remote-tracking branch 'origin'