command: remove extra space

Signed-off-by: wm4 <wm4@nowhere>
stream: tweaks to network reconnection code

Don't reconnect to the cache (since the cached stream already handles
reconnection). This is necessary, because since commit 0b428e44 the
"streaming" field (which also controls whether attempting to reconnect
makes sense at all) is inherited to the cache stream wrapper.

Also, let the stream reset its own position on reconnect. This removes
some assumptions and messy handling from the reconnect function.

Make sure the cache is dropped on reconnect. This takes care of
readjusting the stream position if necessary. (Also drop the cache on
DVB channel switching commands.)
bstr: preparation for next commit

Just so I can move this file without modifying its contents in the next
commit.

compat/compiler.h is to be moved to osdep/ with the next commit, so add
a dummy header.
Move compat/ and bstr/ directory contents somewhere else

bstr.c doesn't really deserve its own directory, and compat had just
a few files, most of which may as well be in osdep. There isn't really
any justification for these extra directories, so get rid of them.

The compat/libav.h was empty - just delete it. We changed our approach
to API compatibility, and will likely not need it anymore.