Adjust PID tune timeouts and thermal watchdog

- Updated readme
- Adjusted WATCH_TEMP_PERIOD to be more tolerant
- Raised PID tuning timeout
- Adjusted default PID tuning commands
- Changed hex file naming

Marlin/Configuration_adv.h

@@ -90,8 +90,8 @@
    * and/or decrease WATCH_TEMP_INCREASE. WATCH_TEMP_INCREASE should not be set
    * below 2.
    */
-  #define WATCH_TEMP_PERIOD 35                // Seconds
-  #define WATCH_TEMP_INCREASE 5               // Degrees Celsius
+  #define WATCH_TEMP_PERIOD 60                // Seconds
+  #define WATCH_TEMP_INCREASE 3               // Degrees Celsius
 #endif
 
 /**