[HYPERLINKS] Adding an ALT parameter to the spec

[Jose E. Marchesi]

[I don't think there is any place where to discuss the terminal
 hyperlinks protocol, I mean aspects that are not specific to poke nor
 the app:// protocol.  Should one be created? :)]

Hi Bruno.

I have a proposal for the hyperlinks spec (note, not the app://
protocol).  In the spec:

  ESC8;PARAMS; [...] ST

Currently the only defined parameter is ID.

My proposal is to allow another parameter: ALT.

Rationale: in the poke protocol we try to not leak information in the
hyperlinks by only emitting a token number.  Therefore our links look
like:

  app://host:port/12345

However, this has the undesirable side-effect of not giving any
indication on what the hyperlink does.  The "alt text" shown by my
hyperlink-capable terminal is just the URL.

With the new parameter we could emit:

  ESC8;ALT=delete this IO space; [...] ST

And the user would see the alt-text "delete this IO space" when she
hoovers the mouse over the hyperlink.

WDYT?