operational segregation improvements
DOCS-860 add the cursor.addOption method
DOCS-860 addOption method, includes warning
positional and elemMatch projection operators
incorporate ben's comments for elemMatch and positional projection operators
incorporate Jeff's comments
DOCS-368 projection operators position and elemmatch
Fixed tiny typo
DOCS-1016 document missing sharding shell helpers
DOCS-860 cursor.addOption
DOCS-860 addOption shorten example to add only one option
DOCS-461 configure behavior of balancer
merge: DOCS-860
DOCS-368 projection operators -  incorporate git comments
DOCS-461 review edits
minor: updates to chunkSize in mongos man page
clarifications of how to resync if stale in a replica set. also removed mention of fsyncLock() as it often blocks the other server so it can only be used with care and thus you would really have to go read the full backups page before using it
Merge branch 'master' of github.com:mongodb/docs
DOCS-934 centerSphere and within
DOCS-934 review edits