Fix a deadlock between background and network threads.

We paused the background threads by holding a lock across reconfiguration.
Unfortunately, we did so by first blocking the threads and then the network
traffic.  If a packet arrived that required passing info to the background
threads (by holding their lock), we could deadlock.  Fix this by adding another
set of condition variables between the background threads and the thread that
performs reconfiguration.
Fix an off-by-one that made the client aggressively request new configurations
removed deprecated dist-lzma from autoconf

Upstream autotools has removed dist-lzma as of 2.69; this prevents generating a configure script with the following error:

    $ autoreconf -i
    configure.ac:6: error: support for lzma-compressed distribution archives has been removed
    ... ellided install output ...
    autoreconf: automake failed with exit status: 1

See the automake manpages for more info.
Documented dependency on gperf for git builds

When building from scratch on Arch Linux, autoreconf and configure will pass without gperf installed.  This should be documented as a requirement for building from git.
Added a pkg-config file for hyperclient
removed spurious requirements from hyperclient.pc
make error messages for "hyperdex" more useful
This commit and all previous that I have authored are signed off by me

Signed-off-by: Scott Dunlop <swdunlop@gmail.com>
Increase write buffer size
Reorder ACK with I/O where we can get away with it

Nodes inside the chain don't need to ack before putting an object to disk
Fix perms
Merge branch 'master' of git://github.com/swdunlop/HyperDex

* 'master' of git://github.com/swdunlop/HyperDex:
  This commit and all previous that I have authored are signed off by me
  removed spurious requirements from hyperclient.pc
  Added a pkg-config file for hyperclient
  Documented dependency on gperf for git builds
  removed deprecated dist-lzma from autoconf