change main entry to caracal.js

[YashKumarVerma]

fixes #71

Description

• changes entry point of application

Motivation and Context

• now running node . does not throw any error.

How Has This Been Tested?

• tested locally.
• does not interfere with the testing suite.

Screenshots (if appropriate):

Types of changes

**What types of changes does your code introduce? Put an x in all the boxes that apply:

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist:

**Go over all the following points, and put an x in all the boxes that apply.
**(If you're unsure about any of these, don't hesitate to ask. We're here to help!)

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.

[birm]

Good catch!