media-sound/csound-9999: updated

media-sound/csound-9999: updated

 1) updated to eapi7
 2) removed python2_7, added python3_{5,6,7,8}
 3) removed temporarily java use flag as building java interface
    does not work atm due to missing configuration variables
 4) updated and organized deps
 5) removed csoundac use flag as it does not have corresponding
    configuration in cmake
 6) added most of configurable options from cmake for future
    reference
 7) reorganized cmake flags so they match the alphabetical order
    of their names so they can be easily match in cmake-gui
    for example
 8) added -DFAIL_MISSING=ON so that the ebuild fails when a dep
    is missing
 9) removed cmake flags that are not present anymore
10) added selection of correct lua implementation based
    on lua and luajit use flags

Package-Manager: Portage-2.3.81, Repoman-2.3.20
Signed-off-by: Miroslav Šulc <fordfrog@gentoo.org>