[Tracker] Simplifying DBus interface

["Samuel Cormier-Iijima" <sciyoshi gmail com>]

I had a strange idea: what if all (or most) search methods were SQL
queries implemented client-side? i.e. if DBus had one real method such
as ExecuteQuery, and the client library had a wrapper which created
the right queries? this would radically simplify the DBus interface,
and would allow executing more exotic queries also. the live query
interface would still have to be implemented "server"-side though...
at worst, could you include such a method? it would be fun to execute
queries on my indexed filesystem :-)

Samuel