Implement sqlite3_total_changes

[gismofx]

I would like to use sqlite3_total_changes when executing multiple statements within a transaction. Can this be implemented?

As a work-around, I am cumulating changes function after executing each statement.

[schickling]

Should be easy enough to expose yourself in a fork and possibly @rhashimoto would be open to a PR for this.

[rhashimoto]

As a work-around, I am cumulating changes function after executing each statement.

This missing function is similar to sqlite3_clear_bindings(): there is no wrapper function, the underlying C function is exported by the WebAssembly module (the argument to SQLite.Factory() creating the API wrappers), and the argument and return value are simple integers. So perhaps a more convenient workaround would be to call module._sqlite3_total_changes(db).

I'll put adding a wrapper on my TODO list at low priority. Or as @schickling suggests, I'd be open to a PR (with a test).