DOCS-1416: clarifiying journal commit interval
DOCS-1426 remove fields and fieldFile options from mongooplog

Signed-off-by: Sam Kleinman <samk@10gen.com>
minor: dtf fixing test
DOCS-1422 fixing cross reference.
minor: build adding requirements.txt file for repo
Fixed some grammar in the convert-secondary-into-arbiter.txt doc file

Signed-off-by: Sam Kleinman <samk@10gen.com>
DOCS-1053 array and compound conditional operators

Signed-off-by: Sam Kleinman <samk@10gen.com>