perl plugin: #undef macros before poisoning them.

This fixes --enable-debug builds.
curl_json plugin: don't complain about not finding expected maps in arrays

The arrays may have mixed maps and scalars.  I'm looking at you Solr.
Add a plugin for monitoring zookeeper

This adds a simple plugin to read data from Zookeeper's MNTR
command to allow for easy monitoring of Zookeeper from collectd
without requiring jmx
Add information to collectd.conf (5) for the zookeeper plugin
Use generic types for a few more of the zookeeper metrics
Merge pull request #396 from radford/perl-debug-compile-fix

perl plugin: #undef macros before poisoning them.
Renamed all CPU_STATE_* defines for consistency and to avoid conflicts (fixes #812)
Merge pull request #829 from njh/cpu_state

Renamed all CPU_STATE_* defines for consistency and to avoid conflicts
Merge pull request #411 from radford/curl-json-inhomogeneous-arrays

curl_json plugin: don't complain about not finding expected maps in arrays
cpu plugin: Fix ValuesPercentage to behave as documented.

The documentation claims that ValuesPercentage is only considered when
!ByState && !ByCpu. Fix the behavior to match this documented behavior.
This makes cpu_commit_without_aggregation much easier.

Bug: #820
cpu plugin: Mark the "active" state as available.

This fixes the !ByState && ByCpu case, i.e. when the user requests one
metric ("active") per CPU.

Bug: #820
Merge pull request #826 from katzj/zookeeper

Add a plugin for monitoring zookeeper