Use a generic description for non-GitHub hosts

[tribut]

The HTMLWriter currently uses

for the source link, even if the repo points to a private host (such as a self-hosted GitLab instance). This PR changes the default to simply

in case no known host is detected.

[mortenpi]

This is a good idea. The current implementation will take away all GitHub links though, since the default repo template is defined in the url function. It should probably be moved away from there and made the default argument for doc.user.repo. I don't know if doing that will change any other default behaviour though.

Documenter.jl/src/Utilities/Utilities.jl

Lines 386 to 389 in c58e7e0

	function url(repo, file; commit=nothing)
	file = realpath(abspath(file))
	remote = getremote(dirname(file))
	isempty(repo) && (repo = "https://github.com/$remote/blob/{commit}{path}")

One other minor thing -- having just the work "Edit" looks somehow too narrow. What do you think about having something like "Edit source"?

[tribut]

"Edit source" seems fine, I've update the PR accordingly.

However, I do not understand how my changes would take away Github links. Looking through the code, the url function is called twice, namely:

Documenter.jl/src/Writers/HTMLWriter.jl

Line 445 in b598cb0

url = Utilities.url(ctx.doc.user.repo, pageurl, commit=ctx.doc.user.html_edit_branch)

and

Documenter.jl/src/Writers/HTMLWriter.jl

Line 725 in b598cb0

url = Utilities.url(ctx.doc.internal.remote, ctx.doc.user.repo, result)

In both cases I cannot see how the repo argument would be different after my changes?

[mortenpi]

I was a bit imprecise: GitHub links get the generic icon. They don't disappear.

And the reason is that url gets called after

Documenter.jl/src/Writers/HTMLWriter.jl

Line 427 in b598cb0

host_type = Utilities.repo_host_from_url(ctx.doc.user.repo)

and so at that point ctx.doc.user.repo is an empty string and does not match the GitHub repo.

The URL handling is a bit hectic and should probably be refactored at some point. But for now, to work around this issue, just make the GitHub part of Utilities.repo_host_from_url into the following:

elseif occursin("github", repoURL) || isempty(repoURL)
    return RepoGithub

Utilities.url seems to use the same heuristic to determine that it should create GitHub URLs.

[tribut]

Oh, yes. Empty repo would have had that effect, yes. I've updated the PR as you suggested.

[mortenpi]

LGTM, thanks!