Add proper licences for activated chapters

[eAlasdair]

Resolves #910
Related to #451

Note that in most cases this does not update interactive READMEs, as there are unrelated issues with them also.

Reviewers, please pay close attention to items in the list with associated notes - their licences deviated from the norm in some way and I could have improperly licensed them as a result.

Added Licences for:

• Base Dependencies
  • Bootstrap
  • jQuery
  • Details Element Polyfill
  • Featherlight
  • Popper.js
  • Multiple Select
  • StickyState (no LICENSE found, assumed MIT from npm - issue here)
  • iframe resizer
• FSA module
  • es6 ArrayMap
  • Underscore
• Development Dependencies
  • autoprefixer
  • @babel/core
  • @babel/preset-env
  • browserify
  • removed child_process from the project (issue with source here)
  • del
  • gulp
  • gulplog
  • gulp-babel
  • gulp-filter
  • gulp-if
  • gulp-jshint
  • gulp-error-handle (no source found beyond npm, MIT licence assumed from npm - see here)
  • gulp-notify
  • gulp-postcss
  • gulp-rename
  • gulp-sass
  • gulp-sourcemaps
  • gulp-tap
  • gulp-terser
  • gulp-util (deprecated see here)
  • jshint (JSON Licence mentioned in npm but only MIT stated in source)
  • jshint-stylish
  • puppeteer
  • request
  • node-gyp
  • postcss-flexbugs-fixes
  • run-sequence
  • vinyl-buffer
  • yargs
• Libraries required for specific interactives
  • Algorithms chapter
    • Sorting Algorithms
      • Dragula
  • Data Representation chapter
    • Unicode Binary
      • urijs
      • underscore.string
      • string.fromcodepoint
    • Unicode Chars
      • string.fromcodepoint
    • CMY Mixer
      • nouislider
      • wnumb
    • RGB Mixer
      • nouislider
      • wnumb
    • Colour Matcher
      • nouislider
      • wnumb
  • Coding Compression chapter
    • Huffman Tree
      • viz-lite (source file)
    • JPEG Compression
      • interactjs (alpha)
      • dct
  • Coding Encryption chapter
    • Big number Calculator
      • big.js
    • Caesar Cipher
      • es5-shim
      • es6-shim
    • Frequency Analysis
      • chart.js
      • es5-shim
      • es6-shim
    • RSA no padding
      • jsencrypt
    • SHA2
      • crypto-js
  • Unspecified Chapter
    • RSA JSencrypt
      • jsencrypt
• requirements/base
  • wheel
  • Pillow
  • django-inline-svg
  • selenium
  • Verto
  • python-markdown-math
  • django-haystack (License file not found - copyright holder stated on their website)
  • Whoosh
  • django-widget-tweaks
  • lxml
  • cssselect
  • PyYAML
  • django-modeltranslation
  • uniseg
  • python-bidi
  • django-bidi-utils
  • django-statici18n
• requirements/local
  • sphinx
  • sphinx-rtd-theme (several license files included here, only MIT listed)
  • django-debug-toolbar
• requirements/test
  • flake8
  • pydocstyle
  • coverage
  • django-test-without-migrations
• other
  • Django (includes 'code from the Python standard library')

[JackMorganNZ]

@eAlasdair For child_process, the only place it is used is to make a beep sound on a error, which I don't think we've ever implemented. We don't need a audio error sound, visual text is fine, so easiest solution is to remove it:

• csfieldguide/package.json - Remove line 42.
• csfieldguide/gulpfile.js - Remove line 21, 54 to 65, and 68.