tracker-miner-fs: Interpret GFileInfo times as time_t
This is a time_t underneath, and forcibly interpreting it as unsigned will break with negative times on platforms that internally define that type as signed (Linux and the GNU C library between them).
Deal with it as a time_t on our side, and let up to the underlying implementation the interpretation of negative timestamps.
Fixes: #155 (closed)
Edited by Carlos Garnacho