MCP230XX driver and examples are all broken

[rwaldron]

Before attempting to run any code, I rebuilt everything.

I'm not sure which commit broke the driver and I'm having trouble finding a "last good commit" (even when I go back to my last commit to this code, I get unrelated errors). This commit 61315cb introduced alout of changes, but I currently cannot pinpoint the exact cause of breakage.

This commit 923feab broke the examples, because now there is no module "pins/digital" to import from.

A lot of code churn is happening, and that code is getting merged without being tested against real hardware, in all configurations that will be affected. When I was writing this driver, I ran every single change against 5 different hardware setups:

• Single MCP23008
• Multiple MCP23008
• Single MCP23017
• Multiple MCP23017
• Combo MCP23008 & MCP23017

I did this testing to ensure that my changes didn't introduce regressions. I tested these same configurations for the follow patch as well.

[phoddie]

I believe these are currently working. If you encounter issues, please re-open. Thanks.