Add NaN handling config options
input/collectd: Implement handling of NaN values
Add tests for the collectd NaN handeling
input/collectd: Better tagging on NaN

  * Don't overwrite existing tags
  * Allow the user to config the tag to add when a NaN is found
touch up statsd output
Fix percentiles on metrics filter
explain defaults
touch up
Added option to disable certificate validation

If a IMAP-server is using a self-signed certificate, this patch adds a "verify_cert" option to the module that is by default set to true (old behavior), but if set to false it will disable the verification check. The result is that IMAP TLS with self-signed certificate will not crash logstash.
Added option to disable certificate validation
Added warning when registering insecure state
Change [A|a] by [Aa], etc.
Try more times to fetch from rubygems.org

Of the last 14 build failures, 6 of them were because of bad_record_mac.
Hopefully retrying more will work around this.
fix handling of more than 2 repetitions of same mail header
bluecloth is needed to build the docs
json_lines codec documentation is special since it isn't used with the file input.
Also fixed formatting issues with the config examples in the synopsis section.
actually encode to UTF-8 when input charset is non UTF-8 + basic specs
explicit return for explicit explicitness
    Fix bug LOGSTASH-1225 "Cannot Clone Fixnum"

    The clone {} filter will throw an exception if any of the values in the
    event map are numbers. Problem is that numbers are not clonable.

    This is a single-line fix that wraps the .clone call in a try block and
    does a simple set-by-value if the clone raises an exception.

    Included under spec/filters/clone.rb is a test case that fails without
    the change in lib/logstash/event.rb and passes with the fix applied.
Actually clear GEM_PATH

This helps ensure we provide only our own gem directory for rubygems.

Helps improve LOGSTASH-1918. Before this patch, my local ruby install
was accidentally providing 'rack' so I never noticed this problem.