WIP: Native GPIO

- dummy and Linux sysfs GPIO drivers for native
- minor PIR driver test fix

TODO:
- [ ] add signal mode for sysfs driver
- [ ] implement writing for sysfs driver
- [ ] test sysfs driver on raspberry PI
- [ ] add control method for dummy interface
- [ ] address sysfs GPIO availability issue
- [ ] guard native system calls
seems to work, TA!