JMPLAYER R2.7d

Fix the MIDI button acting on the wrong song while paused

Reported as "the previous song plays when switching between FM and
MIDI". patchTargetPath() asked only isPlaying, but a paused song has
isPlaying false while still being the song on screen - so pausing moved
the button's target to whatever row was highlighted in the playlist,
which during playback is usually a different song. Toggling wrote the
mode onto that file, left the loaded one alone, and the next play
started the highlighted song.

m_pausedByUser is what separates a pause from a stop, so the target is
now chosen by "isPlaying || m_pausedByUser".

The same guard had a second effect: toggling while paused changed the
flag but not the loaded stream, and playPause() would resume the old
engine under the new label. A paused song is now stopped, so the next
play loads it through the engine actually selected. F5's
rebuild-on-close carried the identical guard and got the same fix.

Also brings in midiall, the fourth test tool: MidiPlayer's parse, tempo
map, sound-mode verdict and lyric decoding over 7,884 containers and a
sample of the 116,085 .mid files. It would not have caught this one -
transport state is in the UI, which none of the tools can see.