top(1): Start parsing colors

[eadler]

Summary

This starts off parsing colors in a manner similar to that documented in
newer versions of the original top(1).

• currently unimplemented: actually using the color
• it doesn't deal well with malformed TOPCOLOR strings

I wanted to get some early feedback though.

ref D15801 for what's blocking making use of the colors

[eadler]

add documentation stub to remind me to write more

[bcr]

Would it make sense to add an EXAMPLES section that shows how to define a proper TOPCOLOR?

[eadler]

In D15960#338171, @bcr wrote:

Would it make sense to add an EXAMPLES section that shows how to define a proper TOPCOLOR?

yeah. This isn't done or documented. Just threw this up here in order to (a) get feedback and (b) not lose it.

[0mp]

I think I've found some issues with mdoc formatting in the manual page.

usr.bin/top/top.1

196

Shouldn't there be a newline after ".Nm"?

Also, it should be Ev TOPCOLOR.

197

Ev TOPCOLOR

383

Shouldn't we use Ev instead of Pa here?

384

Missing period at the end.

Also, shouldn't we replace top with Nm here?

385

This should follow the "Default set of arguments to" line.