Mod Remapping API

Dropped Fabric Loader 0.14 support.
Improved mixin remapping by a lot.
New v2 api featuring:

• Remapping context based on a provided id, shareable by multiple mod remapper.
• ModDiscovererConfigs allowing better mod candidate filtering, multiple can be provided.
• MappingsConfig defining source Namespace, default package, custom mappings and namespace renames for the custom mappings.
• RemappingFlags, available currently: mixins and access wideners.
• Allow registering more ModRemappers dynamically.
• CacheHandler system, allowing to get diverse file locations linked to a RemappingContext
• v2 MappingUtils methods now also take the contextId as argument.
• Access wideners remapping support.
  v0 and v1 apis are still supported but deprecated.