Support workspace creating from repository if it contains .devfile.yaml/devfile.yaml file

[sleshchenko]

Description

Now, Factory API supports only repositories with Devfile if file name is .devfile
https://github.com/eclipse/che/blob/7a9feef2b553fd20ffc85f2a53b8f38b2e75847f/plugins/plugin-github/che-plugin-github-factory-resolver/src/main/java/org/eclipse/che/plugin/github/factory/resolver/GithubURLParser.java#L93
But many editors do not enable YAML syntax highlighting if file name does not have format specified.
I think it is better to add support workspace creating from repository if it contains .devfile.yaml file.

See how it affects displaying by Github

Without format specified:

With format specified:

See how it affects displaying by Atom editor

Without format specified:

With format specified:

Actually, a user may want not to hide Devfile file from file managers, and it would be good to give a user choice and name Devfile as he wants - with dot or without at the begigging of name.

[sleshchenko]

@l0rd @skabashnyuk WDYT?

[garagatyi]

👍 YAML indentation can also be validated to avoid some basic mistakes

[l0rd]

@sleshchenko I amo 👍 for your proposal. But honestly the biggest issue for me is that no error is shown if a file .devfile is not found. At this stage it's ok to support only .devfile but if there is no such file is found (because the user has named it devfile.yaml for instance) an error should be shown:

No valid devfile hasn't been found in the github repository. There is no <URL>/.devfile.

[mshaposhnik]

@lord That is because we still support this kind of factories which pointing to any GH repo, even without .devfile/factory.json/e.t.c. In this case project will be cloned, and defaut plugins applied to the WS conf.

[l0rd]

Thank you for your explanation @mshaposhnik but I don't think we should support that. It's really misleading.

[mshaposhnik]

No problem, if it's decomissioning will be approved by @slemeur

[slemeur]

I'm -1 to remove that.

In fact, that allows to import a project in Che with just a URL even if there is no devfile and factory.

That allows flow like:
{host}/f?{my_repo}

We can't expect that the devfile will be define before the project gets imported in Che.

It should be easy / simple to import in Che and requires the minimum of pre-requisities. Once the developer is in Che, we make the configuration of the workspace easy and allow the developer to version that with a devfile.

Also, Che should be able to analyze the project, detect the technologies used and propose to the user a workspace that fits with his needs.

[sleshchenko]

Is not actual after merge of #12965