DOCS-1595 adding table mapping helpers to their javascript equivalents

Signed-off-by: Sam Kleinman <samk@10gen.com>
DOCS-1595: syntax fixes
fix: xref errors
build: correcting epub and html-tarbal
fix typo in sharding intro, reduce size of chunk split image
fix missing backticks in list table
DOCS-1690: adding note about namepaces to the faq
DOCS-1692 clarification about numbers of mongos instances
DOCS-1693: roles is not optional in new-style auth documents.