more cogent onboarding instructions

Dependencies

• [2] KQWIMWJ5 deemphasize the terminal in Readme
• [3] D4FEFHQC flesh out Readme
• [4] ZTMRQZSW Readme
• [5] CZRMAMSB clearer discription of how to run lines.love
• [*] FS2ITYYH record a known issue

Change contents

• edit in README.md at line 10
  [3.33]

  [3.162]
  +

  + To run from the terminal, [pass this directory to LÖVE](https://love2d.org/wiki/Getting_Started#Running_Games),

  + optionally with a file path to edit.
• replacement in README.md at line 14
  [3.163]→[2.19:58](∅→∅)
  − To run lines.love, double-click on it.
  [3.163]

  [3.222]
  + Alternatively, turn it into a .love file you can double-click on:

  + ```

  + $ zip -r /tmp/lines.love *.lua

  + ```
• edit in README.md at line 24
  [3.505]→[2.120:264](∅→∅),[2.264]→[3.629:630](∅→∅),[3.629]→[3.629:630](∅→∅)
  − lines.love can also be [invoked from the terminal](https://love2d.org/wiki/Getting_Started#Running_Games),

  − optionally with a file path to edit.

  −