nunjucks-loader

• Update readme with default options description
• Add support of globals in template

Fixes:

• Shiny new schema.json that is required for options validation was missing from npm package.

New:

• Add support for base paths, that tells Nunjucks where is templates live;
• Add options validation.

Fixes:

• Rendering of dependant templates of dependant templates actually didn't work before. Now it's OK.

Fix package in npm contains outdated build of loader.

Working demo, with support of basic cases of templates precompile, and webpack chunks creating.