Add redux aa1 to improve basics aa3

[schettn]

Checklist:

• [x] Have you added an explanation of what your changes do and why you'd like them to be included?
• [x] Have you updated or added documentation for the change?
• [x] Have you tested your changes with successful results?

Type of Changes:

• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Documentation (non-breaking change which adds documentation)
• [x] Breaking change (fix or feature that would cause existing functionality to change)

What is the current behavior? (link to any open issues here)

• Currently the sign in button in the navigation bar redirects to the start page, but not directly to the sing in form. #73
• Currently it is not possible to upload custom avatar images. #76
• Currently user settings can be changed via a modal. #77
• Currently when recaching data the avatar image resets. #78
• Currently the application structure does not fit our needs because several issues. #80
• Currently there is no notification when sining in fails. #81
• Currently the pinned repositories are kind of useless because they do not show any useful information. #82
• Currently there are some issues in styling when displaying projects. #83
• Currently there is no language chart for projects. #84
• Currently there is no default image for projects without an avatar image/owner. #85
• Currently there is no language chart for a user. #86

What is the new behavior (if this is a feature change)?

• Now it is possible to upload custom avatar images. #76
• Now user settings can be changed via a separate settings page. #77
• Now when uploading a avatar image it is permanent. #78
• Now redux is implemented which resolves issues like active tabs when state changes,.. #80
• Now when singing in fails there is a notification in the login form. #81
• Now the pinned repositories are temporary disabled. #82
• Now the styling of projects is refined and also works fine with projects without an owner. #83
• Now there is a language chart for each project. #84
• Now there is a default image for projects without a an avatar/owner. #85
• Now there is a language chart on each user profile. #86

Other information:

• 🐍

[schettn]

@snek-at/frontend Just have a look on logically errors or some other invalid stuff. Issues on console logs and/or comments like sections are not part of this PR.

This is taken care of in implement PR!

[pinterid]

Opening the settings page without being logged in should redirect to the login page.

Currently there is just an infinity loading screen.

[schettn]

I have updated the login error message cause it was not very neat to me.