glossary edits

Signed-off-by: Sam Kleinman <samk@10gen.com>
missing space, defeats hyperlink.

Signed-off-by: Sam Kleinman <samk@10gen.com>
Update perform-two-phase-commits.txt

Signed-off-by: Sam Kleinman <samk@10gen.com>
DOCS-2757: clarifying timing of chunk splits
DOCS-2339 enable authentication on a mongodb instance
DOCS-2339 enable auth: add second tutorial