wasi-sqlite

This is a quick hack to get sqlite to build as a CLI application for a-Shell using wasi-sdk.

Based on sqlite-amalgamation-3390200 and inspired by wapm-sqlite, using the __wasi__ symbol to tweak some #ifdefs that are not covered by config.h.

Many thanks to @holzschu for guidance in getting this working and figuring out the right hacks to get the UNIX VFS to work.

Known Issues

Working with moderate (100MB+) databases might fail via the sqlite3 prompt, but doing

echo "<command or query>" | sqlite3 foo.db

...might be a good workaround (at least to do "VACUUM;" and other memory-intensive operations)