Replace crypto mining reference with folding@home

Based on the change originally made by @joelsgp in PR #417, but there
were issues with the original commit message:
- Used an emoji which may cause rendering issues in CLI tools
- Mentioned Bitcoin mining which is inaccurate and contained
unnecessary censorship

example/gamemode.ini

@@ -99,10 +99,10 @@ inhibit_screensaver=1
 [custom]
 ; Custom scripts (executed using the shell) when gamemode starts and ends
 ;start=notify-send "GameMode started"
-;    /home/me/bin/stop_ethmining.sh
+;    /home/me/bin/stop_foldingathome.sh
 
 ;end=notify-send "GameMode ended"
-;    /home/me/bin/start_ethmining.sh
+;    /home/me/bin/start_foldingathome.sh
 
 ; Timeout for scripts (seconds). Scripts will be killed if they do not complete within this time.
 ;script_timeout=10