[jmxfetch] no sc warns on metric limit violation

Do not send service check warnings on metric limit violation. See
[#73](DataDog/jmxfetch#73).

Update CHANGELOG to reflect changes.

Author: yannmh

CHANGELOG.md

@@ -126,6 +126,7 @@ See [#1535][]
 * [BUGFIX] Google Compute Engine: Update hostname to be unique. See [#1736][], [#1737][]
 * [BUGFIX] HTTP Check: Handle `requests` timeout exceptions to send the appropriate service check. See [#1761][]
 * [BUGFIX] JMXFetch: Do not override service checks's `host` tag with JMX host. See [#66](https://github.com/DataDog/jmxfetch/issues/66)
+* [BUGFIX] JMXFetch: Do not send service check warnings on metric limit violation. See [#73](https://github.com/DataDog/jmxfetch/issues/73)
 * [BUGFIX] JMXFetch: Fix collector logs being duplicated to JMXFetch ones. See [#1852][]
 * [BUGFIX] JMXFetch: Fix indentation in the configuration YAML example file. See [#1774][]
 * [BUGFIX] Mesos: Do not fail if no cluster name is found. See [#1843][]
@@ -2079,4 +2080,4 @@ If you use ganglia, you want this version.
 [@ulich]: https://github.com/ulich
 [@walkeran]: https://github.com/walkeran
 [@warnerpr-cyan]: https://github.com/warnerpr-cyan
-[@yyamano]: https://github.com/yyamano
+[@yyamano]: https://github.com/yyamano