MNT: update to deal with API change in ME
MNT: update to deal with API change in ME

This allows our code to work with ME current-master and
pymongo v3

There is a bug in v0.10.0 & pymongo 3 due to a renaming of
`disconnect` -> `close` on pymongo collections.

tacaswell/metadataStore,arkilic/metadatastore,hhslepicka/metadatastore,NSLS-II/metadatastore,tacaswell/metadataStore,NSLS-II/metadatastore,hhslepicka/metadatastore,ericdill/databroker,arkilic/metadatastore,ericdill/databroker