update index.js to address deprecation warning

[mario-merino]

No description provided.

[codecov]

Codecov Report

Merging #4 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master       #4   +/-   ##
=======================================
  Coverage   81.25%   81.25%           
=======================================
  Files           1        1           
  Lines          48       48           
=======================================
  Hits           39       39           
  Misses          9        9

Impacted Files	Coverage Δ
index.js	81.25% <100%> (ø)	⬆️

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[vkarpov15]

LGTM from my perspective but I defer to @niftylettuce

[niftylettuce]

@vkarpov15 what version of Mongoose was countDocuments added? we may need to do a peerDependency with that particular >= version.

Also I think we are missing this from docs on Mongoose with the count -> countDocuments deprecation:

Note that if you migrate from count to countDocuments where are query operators including, but not limited to $where, $near, and $nearSphere that need replaced. See https://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#countDocuments for more information.

[vkarpov15]

@niftylettuce 5.2.0: https://github.com/Automattic/mongoose/blob/master/History.md#520--2018-07-02

See docs: https://mongoosejs.com/docs/deprecations.html#-count-

[paullbn]

Hi!
Will this PR be merged?

[niftylettuce]

@paullbn yes, just need a min

[niftylettuce]

Please use mongoose-slug-plugin newest version 2.0.0:

npm install mongoose-slug-plugin@latest

Versions older than v2.0.0 have the following deprecation message now upon installation:

"If you upgrade to v2.0.0+ please ensure you are using Mongoose v5.2+ or greater"

Any issues please let me know.

cc @paullbn