Update deps with `npm audit fix`

[bsclifton]

Resolves this warning (found via npm audit):

┌───────────────┬──────────────────────────────────────────────────────────────┐
│ High          │ Prototype Pollution                                          │
├───────────────┼──────────────────────────────────────────────────────────────┤
│ Package       │ handlebars                                                   │
├───────────────┼──────────────────────────────────────────────────────────────┤
│ Dependency of │ istanbul [dev]                                               │
├───────────────┼──────────────────────────────────────────────────────────────┤
  1 Update deps with `npm audit fix`
│ Path          │ istanbul > handlebars                                        │
├───────────────┼──────────────────────────────────────────────────────────────┤
│ More info     │ https://nodesecurity.io/advisories/755                       │
└───────────────┴──────────────────────────────────────────────────────────────┘

[SergeyZhukovsky]

++ But we need the same fix in staging branch. We use diff branches for production and for staging.

[SergeyZhukovsky]

travis is failing as well!

[darkdh]

please do not submit PR directly into master
Current branch:
staging branch(staging)
master branch(production)

You will have to submit PR to staging first and then after it is merged you use merge commit to open PR against master.

[bsclifton]

@darkdh OK great - updated 👍

[SergeyZhukovsky]

++

[bsclifton]

@darkdh per your comment above- I merged and then cherry-picked the merge commit into a branch based on master. Here's the PR:
#283