Use pkg-config to find apr, if --with-libapr isn't given a path.

The branch already required pkg-config, so just use it.
Remove obsolete message in configure.in, from 3.1.x release.
Rename 'configure.in' to 'configure.ac'.

The old name has been deprecated for some time.
Allow putting gmetad.py in the foreground, without changing debug level.
Add systemd unit files.
Merge pull request #75 from tomprince/systemd

Add systemd unit files.
force all linux cpu stats to be between 0 and 100.

on our 1500 nodes running rhel6 kernels we get a few of these daily:
  cpu_wio_func: val > 100: 1.15299e+17 ~ 1.84467e+19 / 15999 = (3051596 - 3051599) / (902933030 - 902917031)
which are caused by negative rates from /proc/stat being cast to unsigned.
usually it's cpu_wio_func, but we also see it with cpu_idle_func and cpu_user_func.

this patch range limits all linux cpu stats to 0 -> 100 and stops the huge spikes in ganglia data.
obviously it's not solving the core of the problem (it could be the kernel or ganglia), but either way it's much better than spikes.
First round patch to enable memcached publishing using libmemcached.
Fix memcached dependent build for gmetad.
Merge pull request #76 from plaguedbypenguins/master

limit linux cpu stats to [0,100] to remove huge spikes
Merge remote-tracking branch 'upstream/master' into memcached-publish
Support for memcached pushing metric expiry, if dmax != 0.
Include memcached support in test builds.
Try compiling with and without memcached, for safety.
Cluster in memcached key name, parameter documentation, better debug support.
Merge pull request #78 from jbuchbinder/memcached-publish

Memcached publish support
Merge pull request #77 from jbuchbinder/master

Travis build support for memcached with/without
Make sane variable names for cluster in memcached, check for max key length.
Fix typo.
Fix maximum key length for memcached.