Provide a way for a service to set the effective buffer size for a

Provide a way for a service to set the effective buffer size for a
specified method.

Non-atomic methods accumulate RESULT messages into a buffer, from which
they are flushed when the buffer is about to overflow, or when the
closing STATUS message is issued.

The new osrfMethodSetBufferSize() function allows the service to favor
large buffers (for greater throughput) or small ones (for a lower
latency for the first response).

Since the buffersize is not an absolute limit, the effective buffer
size may be set to zero, in which case each RESULT message will be
packaged and sent in a separate XMPP message as soon as it is ready.

Changing the buffer size has no effect on an atomic method, nor on a
method that returns only one RESULT message.

M    include/opensrf/osrf_application.h
M    src/libopensrf/osrf_application.c

git-svn-id: svn://svn.open-ils.org/OpenSRF/trunk@1993 9efc2488-bf62-4759-914b-345cdb29e865