SQLITE_ENABLE_FTS3 is already defined via `-DSQLITE_ENABLE_FTS3` in
`CFLAGS`, however this approach does not work (compile source below to
verify). Adding `--enable-fts3` as parameter did the trick. FTS3 is required
e.g. by Firefox.

	#include <stdio.h>
	#include "sqlite3.h"

	int main(int argc, char **argv){
		if (sqlite3_compileoption_used("SQLITE_ENABLE_FTS3"))
			puts("yes");
		else
			puts("no");

		return 0;
	}