This implements the image size extension that's quite commonly used:
https://github.com/commonmark/commonmark-spec/wiki/Deployed-Extensions#image-size
This supports specifying...
Both width and height: 
Width only: 
Height only: 
The size is always in pixels (relative sizing does not seem
to be spec'd anywhere).
Using ~~text~~ syntax will strike out the text between the two tildes.
Only missing portion is the terminal rendering of strike through text.
The ansi escape codes for strike through text are \e[9m and \e[29m but
it appears the terminal does not support these. Please correct me if I
am wrong.
I tested that the render_to_terminal function was being called by giving
it bold ANSI escape codes, and that did work so the function is being
called correctly.
Hard line breaks insert a <br /> when two spaces are at the end of a
line. soft line breaks are just regular newlines, but whitespace is now
stripped before and after them
This patch handles the following two rules
1) A delimiter run is either (a) not followed by a Unicode punctuation
character, or (b) followed by a Unicode punctuation character and
preceded by Unicode whitespace or a Unicode punctuation character.
2) A _ can be used to open/close a delimiter run if it's (a) not part
of a left-flanking delimiter run or (b) part of a left-flanking
delimiter run followed by a Unicode punctuation character.
The previous Text::parse was not able to give up on parsing a textual
element, and just leave it as plain text. Because this is a very
important part of markdown, I fully rewrote the parser to support this
without having to backtrack. Also the parser now some other little
features, such ast delimiter runs and flanking.
SPDX License Identifiers are a more compact / standardized
way of representing file license information.
See: https://spdx.dev/resources/use/#identifiers
This was done with the `ambr` search and replace tool.
ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt *
