This changes the database to use sha1 based file names. Its not
beautiful, but this is the BS we have to do to cope with the garbage
that is case insensitive filesystems.
Legacy databases are still honored, if you have them.
This completely restructures the database of terminal types, putting
each terminal in its own file. We also compress the database files,
and use infocmp instead of trying to use the C level API.
The mkdatabase script will rebuild the entire database from the terminfo
files on the system. Individual entries can also be built by simply running
the mkinfo program with the terminal type.
