Added npm badges

Added npm version and monthly download rate badges.

Added support for `should` statements and tagged template literals.

Features:

• Added support for chai's should assertions.
• Added allowTaggedTemplates option

Updated readme

Features:

• Added options description

Npm fix

Version bump to fix npm deployment.

Fixed link to the homepage in the package.json

Features:

• Fixed homepage link in the package.json to fix package page at npmjs.com.

Added npm ignore file

Features:

• Added .npmignore file

Fixed dependencies, updated package.json meta-info.

Features:

• Removed unused requireindex dependency
• Added eslint as a peer dependency
• Added links to this github repo in the package.json