Fix for the ReDOS vulnerability
Fix for the ReDOS vulnerability

notifier is currently affected by the medium-severity [ReDOS vulnerability](https://snyk.io/vuln/npm:moment:20161019). 

Vulnerable module: `moment`
Introduced through: `moment`

This PR fixes the ReDoS vulnerability by upgrading `moment` to version 2.15.2 This upgrade will also fix the following other vulnerabilities:
* [low-severity ReDos vulnerabilty](https://snyk.io/vuln/npm:moment:20160126) in the `moment` dependency.


Check out the [Snyk test report](https://snyk.io/test/github/democracyos/notifier) to review other vulnerabilities that affect this repo. 

[Watch the repo](https://snyk.io/add) to 
* get alerts if newly disclosed vulnerabilities affect this repo in the future. 
* generate pull requests with the fixes you want, or let us do the work: when a newly disclosed vulnerability affects you, we'll submit a fix to you right away. 

Stay secure, 
The Snyk team
DemocracyOS/notifier