TS Refactor & preparations for v0.2.0

[edvinh]

Description

This PR contains a bunch of improvements and full TypeScript support. Due to numerous breaking changes the version will be bumped to v0.2.

Notable Changes

• Full TypeScript support
• A build system for compiling, linting, and formatting TS
• Hooks for running tests and linting before commit & push
• Support for both ES Modules & CommonJS
• Glob support for ignorePaths
• New sloc alias for running node-sloc as a CLI
• A flattened structure for the object resolved from sloc(opts).
• Dropped support for node <8.

Breaking changes

• Dropped support for node <8.
• sloc(opts) now returns null if no files matched the specified path. The previous behavior was to return an object with an empty path array and an empty sloc object: {path: [], sloc: {}}.
• The returned object from sloc(opts) has no nesting anymore. It now returns a SLOCResult containing 6 fields:

  {
  loc, 
  sloc, 
  blank, 
  comments, 
  paths, 
  files
  }