Fixed the method type matching and the handler type matching

[mridang]

The plugin breaks when the method name is in uppercase and if the handler name contains multiple dots.

Here's a snippet from my serverless configuration file that causes the plugin to break.

functions:
  minified:
    handler: handler.mininify
    events:
    - http:
        path: polyfill.min.js
        method: GET
        cors:
          origin: '*'
          maxAge: 86400
          allowCredentials: true

[DianaIonita]

Hey @mridang,

Many thanks for your contribution. Looks good - would you mind quickly adding a test as proof that it works and also as living documentation?
Thanks again!