Merge with upgrated official SDL Mixer

[Wohlstand]

• Various Bugfixes
• MPG123 codec
• Rework of music.c, added super-different Music Interface than implemented in current version of SDL Mixer X
• Using of new SDL's Streamer thing with a clean resampling and a sound conversion

https://hg.libsdl.org/SDL_mixer/shortlog

TODO List:

• [x] Extend Mix_MusicInterface structure with Mixer-X specific functions
• [x] Repair a support for meta-tags printing for OGG, GME, and added for ADLMIDI and OPNMIDI
• [x] Add splitting of post-path extra arguments
• [x] Improve the support for a dynamical MIDI device switching
• [x] Add Mix_PlayChannelTimedVolume and Mix_FadeInChannelTimedVolume, again
• [x] Fix an ability to set limited count of loops on looping OGG files
• [x] Implement missing functions in the header
• [x] Repair VB6 Binding on the Windows
• [x] Re-Implement full seekability for the Wave player
• [x] Re-Implement full seekability for MAD MP3 codec
• [x] Try to implement a full seekability for MPG123
• [x] Re-Implement support for ID3 Tags to retreive Meta-Tags from MP3 files
• [x] Repair seekability support for ModPlug
• [x] Repair meta-tags for ModPlug module
• [x] Re-Implement FLAC meta-tags and full seekability
• [x] Repair full support for path arguments and Open*Ex music interface functions
• [x] Fix broken SMPEG support
• [x] Fix broken Timidity custom paths support
• [x] Repair QMake build
• [x] Fix missing reset of ADLMIDI settings after using of path arguments
• [x] Fix handling of RMI MIDI files

[Wohlstand]

The complete merge is completed and all known issues has been fixed! For now the testing is needed and later polishing of the working code.