Move sample projects to Samples~ folder so they're kept out of builds

[johanhelsing]

Pull request checklist

Please check if your PR fulfills the following requirements:

• Tests for the changes have been added (for bug fixes / features)
• Docs have been reviewed and added / updated if needed (for bug fixes / features)
• No compiler errors or warnings

Pull request type

Please check the type of change your PR introduces:

• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes
• Other (please describe):

Issue Number

Issue Number: N/A

Create or search an issue here: Extenject/Issues

What is the current behavior?

• When installing extenject via upm, the sample projects and all their assets get included in the build, making builds slower and larger.

What is the new behavior?

• Samples are moved to the Samples~ folder where they get ignored by unity when installed via the package manager, and no longer bloat builds:

• This also means the samples can now be imported via the package manager interface:

Does this introduce a breaking change?

• Yes
• No

Other information

• To test this PR, install https://github.com/johanhelsing/Extenject.git?path=/UnityProject/Assets/Plugins/Zenject#fix-samples-in-builds via the "git url" in the package manager interface.

On which Unity version has this been tested?

• 2020.4 LTS
• 2020.3
• 2020.2
• 2020.1
• 2019.4 LTS
• 2019.3
• 2019.2
• 2019.1
• 2018.4 LTS

Scripting backend:

• Mono
• IL2CPP

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CI starts automatically when you open a pull request, but only Releasers/Collaborators can restart a CI run. If you believe CI is giving a false negative, ask a Releaser to restart the tests.

[johanhelsing]

While has a (very simple) conlict with #150, and they're both related to upm, they fix different things. Hopefully, this change should be relatively trivial and non-threatening to non-upm users, so kinda hoping reviewing it will be easier/quicker ;)

[johanhelsing]

Looks like this maybe will break non-upm builds after all, see #24 (comment)

I don't know the non-upm workflow well enough. Perhaps the files could be renamed by the unitypackage build script so they're not ignored?

[johanhelsing]

This issue was for svermeulen/extenject and got hijacked by modesttree after their lawsuit.

Zenject once again seems abandoned closing this and continuing the work here Mathijs-Bakker#51