Dispose disposable objects, hopefully fixes leak

[DavidKarlas]

I profiled app using https://github.com/DavidKarlas/Krofiler/ on Mac which is profiling managed objects, and there was no leak, but memory usage grew... Hence it must be native leak, I notice use of Sqlite, so I looked for usage of using and saw few missing, possibly fixes the leak. I can't confirm because its not clear how long memory grows because sqlite caching and leak.

I suggest comparing with ignore whitespace. https://github.com/countervandalism/CVNBot/pull/63/files?w=1

P.S: This is pretty old mono hence don't want to use new using syntax to avoid problems.

[DavidKarlas]

Probably fixes #13

[DavidKarlas]

I ran for some time, and it kept going up, also look at code for disposing, and looks like it doesn't dispose native part... Hence closing...

[reedy]

This is probably still beneficial as good practice

[DavidKarlas]

Ok, reopened, and removed comment about fixing.