Bug fixes and enhancements

Enhancements:

• #4 Removed lodash from dependency.

Bug Fixes:

• #5 Validation for variables types in normalization.

Bug fix for empty reference field.

Bug Fixes:

• #1 Allow content type to have empty reference field

Contentstack Gatsby Source Release

Release 1.0.0 version of source plugin for pulling content into Gatsby from Contentstack. It helps you query content types and entries in Gatsby using GraphQL.