updated bomber-john mapyaml
updated drop-zone mapyaml
updated training-camp mapyaml
Merge pull request #5703 from abcdefg30/mapyamls-update

Fixed non-existing enemies in mini-games.
separate content install from loadscreen
unify install from CD logic
unify music install and add a download option

closes #4759
# This is a combination of 2 commits.

# The first commit's message is:

unify music install and add a download option

closes #4759

# This is the 2nd commit message:

#merge with unify music install and add a download option
fix Tiberian Dawn CD rip logic

closes #4424
add TrimOrEmpty to avoid NREs
unmount all to avoid write permission problems

fight the new caching mechanism and M$ WindowsTM file systems
don't check for general.mix as it stays unmounted

however still extract it
don't test for scores.mix as it is optional
Intro/Map music is also split across several files here
restart the game instead of unmounting on the fly

avoid more redundancy between the load screens
save a redirect
fix the music list not being populated after CD asset install