React Schemaorg Versions Save

There are no functional changes in this version, but we bump the minimum Node version to 12.0.0, and the minimum EcmaScript version to ES2019.

• Trim down source maps from output package. The actual sources were never packaged in react-schemaorg
• Remove unnecessary tsconfig tsconfig.tsbuildinfo from package.

• Various updates to dependencies.

• Minor fix to support other TypeScript versions in peer dependency.

• Support @graph key (#29, #30)
• Readme fix (#27)

• Document and Support next/head usage, see #23 #24

• Document and Support React Helmet usage, see #19
• Improve structure of repo, including testability, linting, etc.

• Target ES5 instead of ES2015, allowing build toolchains that don't know about "class" syntax to work. #17
• Add an optional "space" property to render JSON-LD #15

• Fixes XSS vulnerability (Issue #9 PR #10)
• As a result, a safe JSON-LD parsing technique in accordance with the JSON-LD standard is used, which escapes characters like &, <, >, ", and ' into their corresponding HTML entities.

Behavioral changes

• Certain characters will be escaped within the JSON-LD into their corresponding HTML entities.
  • Notes:
    • This should be a no-op in most cases as the Structured Data Testing Tool (and other <script type="application/ld+json"> parsers will unescape these)
    • If you're embedding HTML content somewhere in your JSON-LD, rely on this script to escape it, so as to avoid escaping it more than once. (HTML entity escaping is not idempotent)
    • SDTT will actually double unescape content, so you'll only start seeing your data mis-parsed if it was already double escaped and is now being triple escaped.

Updates the schema-dts dependency to accept all versions >=0.3.1. Otherwise, proven to be stable and upgrading to "1.0".