Finished getting automatic merge conflict resolution working in direct
mode. Turned out I was almost there yesterday, just a bug in a filename
comparison needed to be fixed.

Fixed a bug where the assistant dropped a file after transferring it,
despite the preferred content settings saying it should keep its copy of
the file. This turned out to be due to it reading the transfer info
incorrectly, and adding a "\n" to the end of the filename, which caused the
preferred content check to think it wasn't wanted after all. (Probably
because it thought 0 copies of the file were wanted, but I didn't look into
this in detail.)

Worked on my test suite, particularly more QuickCheck tests. I need to
use QuickCheck more, particularly when I've pairs of functions, like encode
and decode, that make for easy QuickCheck properties.