2021-04-14  Masaya Tojo  <masaya@tojo.tokyo>

	Add `Install from the source' section.
	* README.md[Install from the source]: New section.

	Add ChangeLog file.
	* ChangeLog: New file.

	Edit `README.md` file.
	* README.md: Rename title from `extract-green-color` to `Extract-green-color`.
	[Requirements]: New section.
	[Installation]: New section.
	[Usage]: New section.
	[License]: New section.

	Initial commit.