Frontend improvements

Implemented milestone pages to milestone. Created a more uniform layout. Separated a lot of layout into components. Added help-popups. Implemented method to delete active challenge. Created an event-bus and installed mitt. Fixed other bugs.

requested review from @sverrefh

assigned to @vildemv

added 7 commits

• a5360c7e...cb177fee - 6 commits from branch master
• 82db9d1e - Merge branch 'master' into 'milestone-page'

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added 1 commit

• cb73af79 - Fixed merge.

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added 1 commit

• a810b89e - Fixed merge.

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approved this merge request

merged

mentioned in commit 097e16a3