As suggested by Joshua, this commit adds the 2-clause BSD license as a
comment block to the top of every source file.
For the first pass, I've just added myself for simplicity. I encourage
everyone to add themselves as copyright holders of any file they've
added or modified in some significant way. If I've added myself in
error somewhere, feel free to replace it with the appropriate copyright
holder instead.
Going forward, all new source files should include a license header.
It's now possible to create symbolic links! :^)
This exposed an issue in Ext2FS where we'd write uninitialized data past
the end of an inode's content. Fix this by zeroing out the tail end of
the last block in a file.
