Changed iterators to use auto, many of which using range-based loops

Initial work on Pica rendering.

24-bit floating points are used internally for calculations on the GPU, however the current code will still emulate that with 32-bit floating points.
In the future we might want to accurately perform the calculations with correct bitness in the future, but for now we just wrap the calculations around this class.

I wrote most of this for ppsspp, so I hold full copyright over it.
In addition to the original release in ppsspp, this provides functionality to easily extend e.g. two-dimensional vectors to three-dimensional vectors.

This cleans up the mess that address reading/writing had become and makes the code a *lot* more sensible.
This adds a physical<->virtual address converter to mem_map.h. For further accuracy, we will want to properly extend this to support a wider range of address regions. For now, this makes simply homebrew applications work in a good manner though.

GSP: Fix a major regression introduced in ffda035c, due to which no display transfers were triggered at all anymore.

Remove the fancy RegisterSet class introduced in 4c2bff61.

While it was some nice and fancy template usage, it ultimately had many practical issues regarding length of involved expressions under regular usage as well as common code completion tools not being able to handle the structures.
Instead, we now use a more conventional approach which is a lot more clean to use.

Use pthread_set_name_np() on OpenBSD.

Gsp command synch

GPU: Updated g_last_ticks variable to be more descriptive (represents CPU tick count of last vertical line).

GSP: Cleaned up code and added additional comments.

GSP: Removed unnecessary TODO comment.

GSP: Changed u32 iterators in TriggerCmdReqQueue to unsigned.

- Various other cleanups.

Core: Added a comment to explain the logic for the RunLoop iterations.

Fix memory unaligned reads

- Unused code
- Was not correct for unaligned memory reads