NgForm annotations seem incorrectly formatted in Dartdoc

[jcollins-g]

@leonsenft

The annotation formatting is hard to read, here.

https://pub.dev/documentation/angular_forms/latest/angular_forms/NgForm-class.html

[jcollins-g]

The main issue here I think is that we want to display something useful (like for @Deprecated, the text string as to why). The current way we do so, by just copypasting parameters into the docs, is not very helpful.

[jcollins-g]

One way to solve this might be to define specific "annotation renderers" to each annotation to whom we care about rendering this way. I could even imagine some sort of like matching on the constructor signature of an annotation to select a renderer, with the first one we implement just a string renderer for a string parameters.