[sqlite] How to enable shared cache mode?

[Aaron Hudon]

I'm looking for a way to enable the shared-cache locking model in 
system.data.sqlite.  http://www.sqlite.org/sharedcache.html

I've looked through the source, and see there is a method in 
UnsafeNativeMethods.cs that exposes this internally to the assembly, but 
nothing that's public.

E.g.
    internal static extern SQLiteErrorCode sqlite3_enable_shared_cache(
        int enable);