Update source/tutorial/perform-two-phase-commits.txt

Fixed the word order
intersphinx: improvements
2.4: removing errant mentions of 2.4 in mainline.
merge: minor correction
DOCS-1033: correction
DOCS-1034 correction
Better sense.
build: fixing link problems
No idea why I get this .Merge branch 'master' of github.com:mongodb/docs