Fix #30 - Add protection against permanent sync locking

A client used to be able to hold the server hostage, preventing other clients from doing an upstream sync, if they disconnected during their sync. This fixes that problem.
Update unit tests for sync locking.
Fixes #11 - Server side client-to-server testing
Added linting to npm test command
fixing issue #26
fixing issue #111
Merge pull request #113 from yoavgurevich/issue111

Issue #111 fixed
Merge pull request #110 from yoavgurevich/issue26

fixed issue #26
Fixed #7 - Deployment of MakeDrive client-side package