python - pq: Use consistent doc-strings for the two buffer

Log Message:
-----------
Use consistent doc-strings for the two buffer implementations.

Modified Files:
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pq/src:
buffer.c (r1.3 -> r1.4)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/python/pq/src/buffer.c.diff?r1=1.3&r2=1.4)
buffer.py (r1.3 -> r1.4)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/python/pq/src/buffer.py.diff?r1=1.3&r2=1.4)