Colorful logs and other related things

[StanHash]

This truly is ColorzCore now

This changes multiple things related to how stuff get logged:

• No Errors/Warnings/Messages sections anymore. Instead, to each message is assigned a tag and can be show up in any order.
• error/warning/messages are now printed during parsing/interpretation (as opposed to when it's done). This way, for very long assemblies, the user will potentially be aware of issues earlier (it also makes the whole thing slightly more manageable internally imo).
• error/warning/message tags are very colorful!
  • This can be disabled using the --no-colored-log program option, in case it causes issues. (It is also automatically disabled when an -error file is given).
• file locations now follow the more "standard" <filename>:<line>:<col> format rather than the verbose File x Line y Column z one. This is because some terminals/terminal emulators (especially when integrated in a text edit, such as VSCode which I use) will allow you to ctrl-click or something that to go directly to the target file+line+col which is neat.

Internally, all logging logic has been moved to a new IO.Log class. It handles formatting and printing messages and stuff.

[Crazycolorz5]

Very nice; I like the abstraction.

Maaaaaaay be worth queuing the writes as before so errors show up last (so that they can be seen separate from others)?

That said, I'm going to merge this as-is, seems fairly reasonable.