gpio driver: update with interrupt functions
gpio module: set strict 32-bit access define
de0 nano: swap GPIO core used, add sw tests, add input-only lines

Swap out the previously-used GPIO core for the OpenCores-based core.

Change config so the 8 LEDs are connected to the I/O lines, and 5 more pins (pushbutton, 4 DIP-switches) are accessible via this core.

Update the pin constraint files for this new layout.

Update top-level testbench.

Add some software for simulation and the board to test both basic GPIO features and interrupts.

New GPIO core is on the 32-bit bus arbiter, so the system's bus arbiters required a change.
de0 nano: get software makefile to pull in main board port makefile fragment
prontoespresso build: update board.h for GPIO driver
mor1kx debug test: make work, add test

Add test for a jump-to-self set of instructions.
Fix the software for the test, too.
de0 nano: add GPIO, 3-wire SPI support

Add some GPIO inputs.

Add 3-wire SPI support on SPI2 block for accelerometer.

Some top-level and testbench cleanup
de0 nano: board.h updates

Add bootrom SPI flash boot delay.

Add SPI driver defines
de0 nano: adv debug defines remove JSP
de0 nano: backend TCL pinout updates

Add some pins to GPIO.

Remove a high tie to the accelerometer chip select because we want to use it in 3-wire SPI mode

Add SPI2 pinout file
de0 nano: add simple-spi code

This also includes code which controls the peripherals on board, such as the accelerometer
gpio driver: add function to get status of interrupts
mor1kx interrupt driver:  add function to clear interrupts in PICSR
bootrom: add ability to delay loading from bootrom
de0 nano: add cof file

This can be used as an example (instructions are embedded
in it) to create a flash image for the board's configuration
flash
de0 nano: update cof file with instructions