still more Andrew Termux/Android mods
rest of Termux related mods from Andrew
fixes for checkin 2 times ago
additional TERMUX related mods from Andrew
add BC_SCALE env var for hi def monitors, cleanup theme data
render effect segv, drag chkbox track coords, check mask active, crop vattachment vfrm copy, gl flip_y coords twice, mask segv if no tracks armed, always ins clip at pos 0 in load append new trks, change load mode text to Paste over selection, add gl_probe for shader lang version 4.3, titler updates gui if ovly coords change,
initial commit