Fix .gitattributes settings and spurious ids.
Fix buffer handling for partial updates (fix #1).

Calls to sha3-update that did not completely fill an already partially
filled buffer were handled incorrectly, in that the buffer-index wasn't
properly updated. Thanks to Orivej Desh for the bug report.
Remove superfluous final iteration in sha3-update.

The superfluous last iteration when start = end wasn't harmful, since the
iteration body winds up as a no-op in that case anyway, but wasn't
intended or needed.
Update NEWS for 1.0.2 release.