32blit

* Significant code refactor and fixes by Ali1234
* Metadata dump fixed to support RL images
* Bugfix to incorrect transparent colour being selected
* Configurable empty_tile for .tmx maps - specifies a tile ID for unset/empty tiles to be remapped to
* Optional struct output type for .tmx maps with width, height layer count and empty_tile
* .tmx map layers are now sorted
* Should not break compatibility, but use 0.4.x if you don't need the new features

:warning: This update breaks backwards compatibility with previous firmware versions. You will need v0.1.6 Beta of the 32Blit firmware or greater to use these new fields.

This update adds URL and Category fields for better discoverability of games/apps and their source.

An additional multi-value field has been added to supply a list of file extensions that a game supports- as of firmware v0.1.6 beta 32blit's launcher is capable of finding the right (installed)application to launch a specific file.

* Breaks metadata compatibility with previous versions!
* Add URL field for GitHub URL
* Add Category field to categorise games/apps
* Add file associations field to identify supported filetypes

* Allow use of user-specified serial port if VID/PID are empty
* Support handling multiple sets of options in CMake tool

* Fixed "32blit game.blit" to *save* (to SD) instead of *flash* again

* New: RLE Encoding support for spritesheets
* Flasher: refined shorthands- "32blit flash game.blit" and "32blit game.blit" will flash a game.
* Flasher: fixed a bug where it would reset an open connection and break during a flash

* New: Version tool: 32blit version
* Packer: Format support for wildcard asset names

Wildcard asset names support the following tokens:

* `filename` - just file name, without extension
* `filepath` - full file path, without extension
* `fullname` - just file name, with extension
* `fullpath` - full file path, with extension
* `type` - asset type, eg: "map"
* `subtype` - asset subtype, eg: "tmx"

For example, the following `assets.yml` and two level files `assets/level01.tmx` and `assets/level02.tmx`:

yml
assets.cpp:
prefix: asset_
assets/level*.tmx:
name: "{type}_{filename}"


Will output:

c++
extern const uint8_t asset_map_level01[];
extern const uint32_t asset_map_level01_length;
extern const uint8_t asset_map_level02[];
extern const uint32_t asset_map_level02_length;