Add support for FLE to mongo tools

Add FLE support for mongodump, mongorestore, mongoimport, mongoexport.

Scenarios

• Add an option to decrypt FLE encrypted data in a collection using mongoDump or Export, using the keys and encryption options stored with the data (automatic decryption).  (e.g. There is encrypted data in the collection but when user dumps or exports the data should be in the clear)

• Add an option to encrypt data in a collection using mongoRestore or Import, using the keys and encryption options specified in the schema (e.g. There is clear text (unencrypted data) in the dump or export that should be encrypted when restored or imported into the collection)