Release v5.0.0

[MikkCZ]

• refresh the intro page with focus on the context features (context menu, address bar icon, links in the toolbar button popup) and add screenshot to assets in the repo
• update screenshots in AMO and Chrome Web Store pages
• update screenshots on the wiki
• follow the new release procedure https://github.com/MikkCZ/pontoon-addon/wiki/How-to-release

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Notable changes in this specific release (since v4.8.1):

• Show page action content in the toolbar button #137 / Show project links in the toolbar button #211
• Screenshots in add-on stores and on the wiki are outdated #201 / Update screenshots and images in the introduction tour #213
• many dependency updates by Dependabot