IBEX IOC Building Training Course

As someone joining the IBEX project (for however long) who will be involved in the development of IOCs I'd like a training guide to help me get to grips with IBEX and building IOCs within it.

**Acceptance Criteria**
1. There is a training guide (presentation, easy to understand wiki page, similar) that details how to create a simple IOC within IBEX

**Notes**
1. The RIKEN DIO system could be reused for this, time and again and cleared out as required - this would provide an actual device on an Arduino that can provide signals between ports on that board
1. This could be written to not need a device at all, which might be more practical
1. Ideally, this will be in place by the start of August 2020