- Core info cache can now be enabled/disabled on all platforms via a new `Settings > Core > Cache Core Info Files` option
- Core info cache file has been renamed from `.cache` to `core_info.cache` (i.e. it is no longer a 'hidden' file on Unix platforms, so can be deleted easily)
- The core info cache file is now compressed (rzip) to further reduce disk IO
- The presence of a `core_info.refresh` file in the core info directory will force a one-time refresh of the info cache. This file is generated automatically when toggling on the `Cache Core Info Files` option, and we will also add it to core info file packaging such that updating info files (either manually or via the online updater) will force a refresh
- The core info cache no longer contains 'core is locked' and 'firmware missing' data fields; these are 'dynamic' properties that must be determined at runtime
- The 'core is locked' status is now determined on core info intialisation by parsing the core directory listing, rather than by performing indivdual 'lock file exists' checks. This minimises file IO, and greatly improves performance on devices with slow storage
- While parsing the core info cache file, we now avoid unnecessary `strdup()`s when adding entries to the resultant cache list
- Memory leaks (potential and real) have been fixed, and safety checks added
- Build errors have been fixed
