Locations parsing fixes, critters' FIDs new methods

• fixed parsing int32_t field for the map locations
• added convenient methods and types to deal with critters' FRM files and animation codes

Fixes & improved .MAP parsing API

• fix xIDs / indexes converions
• better .MAP parsing API

Better .LST parsing API

• flattened result struct for .LST parsing.

Map parsing improved

• fixed tiles' indexing when parsing maps
• fixed sprite declaration

Better CMakeLists.txt

• refined project layout: suits better for git submodule cycled usage
• fixed include guards to be unique throughout Yellowcake project

Code fixes & refactor

• code inspection fixes
• code refactor (cognitive complexity fixes)

Code inspection

• code inspections fixes
• added README.md

Support for .MSG files

• reading index, audio filename and description fields

Support for .LST index files

• support .LST entries
• skipping comments
• reading critters' indexes

Fixed memory issues

• buffer overruns fixed
• type casts fixed