Adds a command line option -db-nosync that provides the ability to use mdb.NOSYNC

Basically the `mdb.NOSYNC` option has been used for a while but until now it's been in a custom build, so in order to properly automate the infrastructure it would be nice to have this available in the repo.

A couple things to note about the PR/changes:
- opted to pass the nosync option into Server, to Servlet, and to DB on creation, rather than make `config` available to these lower levels of abstraction
- a single nosync option is used for both factors DB and servlet DB options

@benbjohnson @boourns @orenmazor