add irc links if included in metadata

[haarg]

This implements #1235, adding an IRC link using metadata, mibbit, or freenode's web client.

I think a web client is much friendlier than an irc:// link for the type of users this is trying to reach, but it may be good to present the raw link as well.

I'd prefer to get comments from the people on the issue before merging this.

[oalders]

@haarg Should we ping the people you specifically wanted feedback from?

[oalders]

@ribasushi: care to comment on this?

[ribasushi]

The frenode webclient defaults are rather braindead - instead you want to use the link from #1235 (comment) https://webchat.freenode.net/?randomnick=1&prompt=1&channels=#$1

I am not entirely sure it is prudent to provide support for x_WebIRC. The only reason I did it this way in DBIC is because I am not capable of emitting version 2 meta without ditching MI, and this is another yak to shave I don't have the arms for at this moment, and most importantly - this isn't metacpan's problem.

Basically what I am trying to say is that supporting a shitton of different x_ things is counterproductive, especially when there is no prior art for this. I would be strongly in favor of only supporting the heuristics method and the spec as outlined in #1235 (comment)

Other than that - pretty please!

[haarg]

The various ways IRC data is listed in metadata is due to the different handling of custom keys in meta 1.4 vs 2.0. In meta 1.4 custom keys must start with a capital letter, vs 2.0 requiring x_. The odd variants all seem to be due to this and the various up/down converting of the metadata.

x_IRC (IRC in meta v1) seems the most commonly used variant, so I'm going to stick with just handling that.
I added x_WebIRC support specifically for things that were still using meta v1. It's not hard to leave out, and with the automatic web link generation it shouldn't be a big loss.

[haarg]

This should be good to go now.