This is a trivial port of the SQLite3 database package to the Cryptech
environment. At least for now, this just downloads the source
package, checks that the SHA-256 digest of the source tarball matches
a known value, and builds the package with the options we want.
If we end up making heavier use of SQLite3 as the project progresses,
we may need something more elaborate (eg, to enable SQLite3's "bare
flash" driver), but this should suffice for the moment.
