Added hidable markdown help table and added formatting-help to private messages

[hairlessbear]

This PR uses formatting-help.jade to add a hidden-by-default markdown help table.

I also added formatting-help to private messages, because why not?

[hairlessbear]

I tried to include only the markdown syntax that users were most likely to find helpful. As you can see in the code, there's a commented out row that has the image inclusion syntax. I opted to remove it because I don't think many users use it, but I kept it in the PR just in case others disagree.

[crookedneighbor]

Looking really good. Made just a few tweaks: 681668f

Here's how it looks now:

Anyone have other tweaks they want in before I merge?

[hairlessbear]

If we aren't including the image syntax, we should remove its commented out row from the table and remove its entries from generic.json.

[deilann]

I use the image code quite a bit. I'm not entirely sure why we're not
adding it because it's not used a lot. I'd imagine that would be a reason
to add it: users aren't aware it's available.

On Sun, May 24, 2015 at 9:36 AM, hairlessbear notifications@github.com
wrote:

If we aren't including the image syntax, we should remove its commented
out row from the table and remove its entries from generic.json.

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Reply to this email directly or view it on GitHub
#5268 (comment).

[crookedneighbor]

Image example added in. Notated toward your next contributor tier.

[hairlessbear]

@crookedneighbor Did you use the image example that I wrote, or modify it? I'm asking because the one I wrote displayed the image at full-size instead of resizing it (like what happens in chat), and it is far too large for the table.

[crookedneighbor]

I modified it and used a small image.

[hairlessbear]

Figured as much, just wanted to check. Thanks for the response.