Support for table markdown syntax

[chalin]

Some API pages like the one for DatePipe contain embedded tables, which displays nicely on the TS-side of the docs. Can we get support for tables in Dart API docs too?

This is the table from the DatePipe API page:

| Component | Symbol | Short Form   | Long Form         | Numeric   | 2-digit   |
|-----------|:------:|--------------|-------------------|-----------|-----------|
| era       |   G    | G (AD)       | GGGG (Anno Domini)| -         | -         |
| year      |   y    | -            | -                 | y (2015)  | yy (15)   |
| month     |   M    | MMM (Sep)    | MMMM (September)  | M (9)     | MM (09)   |
| day       |   d    | -            | -                 | d (3)     | dd (03)   |
| weekday   |   E    | EEE (Sun)    | EEEE (Sunday)     | -         | -         |
| hour      |   j    | -            | -                 | j (13)    | jj (13)   |
| hour12    |   h    | -            | -                 | h (1 PM)  | hh (01 PM)|
| hour24    |   H    | -            | -                 | H (13)    | HH (13)   |
| minute    |   m    | -            | -                 | m (5)     | mm (05)   |
| second    |   s    | -            | -                 | s (9)     | ss (09)   |
| timezone  |   z    | -            | z (Pacific Standard Time)| -  | -         |
| timezone  |   Z    | Z (GMT-8:00) | -                 | -         | -         |

which, in GFM is rendered quite nicely as:

Component	Symbol	Short Form	Long Form	Numeric	2-digit
era	G	G (AD)	GGGG (Anno Domini)	-	-
year	y	-	-	y (2015)	yy (15)
month	M	MMM (Sep)	MMMM (September)	M (9)	MM (09)
day	d	-	-	d (3)	dd (03)
weekday	E	EEE (Sun)	EEEE (Sunday)	-	-
hour	j	-	-	j (13)	jj (13)
hour12	h	-	-	h (1 PM)	hh (01 PM)
hour24	H	-	-	H (13)	HH (13)
minute	m	-	-	m (5)	mm (05)
second	s	-	-	s (9)	ss (09)
timezone	z	-	z (Pacific Standard Time)	-	-
timezone	Z	Z (GMT-8:00)	-	-	-

cc @kwalrath

[kwalrath]

Yes, please.

[jcollins-g]

If this is an issue on a large number of pages (or if you're perceiving people are frequently avoiding creating tables because of this bug), elevate to P1.

[srawlins]

The Dart Markdown package supports GFM tables.

[mit-mit]

We are also seeing this for Flutter packages. e.g. https://www.dartdocs.org/documentation/url_launcher/latest/

@jcollins-g @devoncarew I suggest we raise this to P1. WDYT?

[jcollins-g]

Raised to P1 as while this is a not-common problem/feature request, it seems to be high impact.