also add script to generate a summary map license file
new (undocumented) debug commands:
loadmap <mapname>
loads a map directly, easy to use from scripts
debugline <filename> <text>
writes text to file (no path names allowed)
also stripped assaultcube.sh, server.sh and install_or_remove_menuitem.sh
of unnecessary or just wrong stuff
added script to generate checksum file packages/misc/checksums_md5.txt,
which is used by check_install.sh to look for missing and modified files
aurhat