convert videos to gif so they render inline on GitHub

Dependencies

• [2] V366JSXA videos
• [3] TLOAPLBJ add a license
• [4] XX7G2FFJ intermingle freehand line drawings with text
• [5] FS2ITYYH record a known issue
• [6] 73OCE2MC after much struggle, a brute-force undo
• [7] LXTTOB33 extract a couple of files
• [8] 66X36NZN a little more prose describing manual_tests
• [9] D2GCFTTT clean up repl functionality
• [10] BJ5X5O4A let's prevent the text cursor from ever getting on a drawing
• [11] 3QNOKBFM beginnings of a test harness
• [12] R5QXEHUI somebody stop me
• [13] BULPIBEG beginnings of a module for the text editor
• [14] VHQCNMAR several more modules
• [15] AVTNUQYR basic test-enabled framework
• [16] CZRMAMSB clearer discription of how to run lines.love
• [17] RSZD5A7G forgot to add json.lua
• [18] OGUV4HSA remove some memory leaks from rendered fragments
• [19] NONKKVVP update Readme for this fork
• [20] 6LJZN727 handle chords
• [21] OTIBCAUJ love2d scaffold
• [22] BLWAYPKV extract a module
• [23] T4FRZSYL delete an ancient, unused file
• [24] K2X6G75Z start writing some tests for drawings
• [25] 4YDBYBA4 clean up memory leak experiments
• [26] TVCPXAAU rename
• [27] VXORMHME delete experimental REPL

Change contents

• file deletion: before.webm (----------)
  [3.2]→[2.794489:794511](∅→∅),[2.794511]→[2.17:17](∅→∅)
• file deletion: after.webm (----------)
  [3.2]→[2.1989870:1989891](∅→∅),[2.1989891]→[2.794514:794514](∅→∅)
• file addition: before.gif (----------)
  [3.2]
• file addition: after.gif (----------)
  [3.2]
• replacement in README.md at line 21
  [2.1989974]→[2.1989974:1989997](∅→∅)
  − ![before](before.webm)
  [2.1989974]

  [2.1989997]
  + ![before](before.gif)
• replacement in README.md at line 25
  [2.1990039]→[2.1990039:1990060](∅→∅)
  − ![after](after.webm)
  [2.1990039]

  [2.1990060]
  + ![after](after.gif)