small bugfixes and improvements

[the-real-orca]

This is a great project, thanks. I use it to add a display to my DIY spot welder. While configuring it to my welder I made some enhancements.

• bugfix input/output configuration. (When using digitalWrite() Arduino automatically re-configures the pin to output.)
• output pin can be configured to low/high active
• delay and combine EEPROM writes to save write counts