DOCS-2671: new tutorial: deploy replica set and configure authentication and authorization

Signed-off-by: Sam Kleinman <samk@10gen.com>
DOCS-2671: edits and structure for replica set tutorial
DOCS-2671: redirect and edit
DOCS-2671: edits to deploy replica set with auth document in response to spencer's feedback
DOCS-2671: additional clarifications for deploy repl-set auth tutorial
DOCS-2671: syntax fixes
DOCS-2671: fixing logical error in steps sequence
DOCS-2671: deploy replica set steps
DOCS-2671: improvements to the introduction of the repl-set-with-auth tutorial
DOCS-2671: changing langauge in tutorials and introductory materials
DOCS-2671: edits to avoid the localhost auth bypass