Increased payload size of NRPE

Applied the patch from:
http://altinity.blogs.com/dotorg//nrpe_multiline.patch

This adds multiple packets to the nrpe output, allows for up to 16k
characters in status return, and is backwards compatible.

It may have been originally an opsview patch, but I am unsure who the
attribution should ge to. (Potentially "Altinity" from the patch
comments?)

Additionally, we may want to add a new config directive to limit the
MAX_INPUT_BUFFER for those who do not want any check returning more than
a certain size less than the new MAX of 16384.