Autocomplete of adding issues and adding epics to epics

When adding issues or epics to epics, currently you have to paste the link of the issues/epics. This requires you to know the link in advance. This has been referenced in no less than 8 customer calls (as of 10/30/19) as a major blocker for adoption.

If you know the issue or epic title in advance, you could quick search and autocomplete on it. This is the same design we already have when adding related issues:

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