Allow uploading folders in the Web IDE

Release notes

Allow users to upload folders in the Web IDE. This should also allow upload of folders containing nested folders.

Problem to solve

Currently if someone wants to replicate a directory structure on their local machine in the repo, the only way they have is by manually uploading contents of each folder. Allowing uploading a folder directly should make this a simple one step process.

User experience goal

The user should be able to replicate a directory structure in the Web IDE by uploading an entire folder.