Fixed hasAdditionalStacksPlugin check if using modules in plugins sec…

[sampsasaarela]

Fixes _.get(...).includes is not a function error if serverless.yml looks like this:

plugins:
  localPath: './plugins'
  modules:
    - my-custom-plugin
    - serverless-domain-manager
    - serverless-dynamodb-local
    - serverless-offline

[designfrontier]

This is breaking me as well... it appears that this.service.plugins is not an array in the latest version of serverless. Which breaks the check

[vkartaviy]

I have fixed this by using pluginManager, see #222

[AshanFernando]

Thanks @sampsasaarela for the PR. There is another PR #222 for the same purpose sent later on. Will you be able to check whether there is anything we could get from it? I'm approving this, if there are any changes, please incorporate. Waiting for another review before merging.

[sampsasaarela]

Thanks @sampsasaarela for the PR. There is another PR #222 for the same purpose sent later on. Will you be able to check whether there is anything we could get from it? I'm approving this, if there are any changes, please incorporate. Waiting for another review before merging.

I think both will do the job, but my version is not dependent parsePluginsObject, the only dependency is lodash as before and should be fully backward compatible.

[cyberwombat]

Can this be revisited? Still unable to use enhanced plugin setup. Thanks.