Make project and issue type icons available by emoji shortcode

Adding small inline images, like icons and symbols, into Jira issue descriptions and comments or Confluence pages is a hassle, unless one configures them as custom emojis with a colon-flanked shortcode, e.g. `:story:`. They are then available across the whole company cloud site at Atlassian.net.

There is of course a plethora of such pictures that users could wish for, but I think there is a baseline that could be made available automatically:

• I wish all icons configured for Jira projects were made available as either case-insensitive `:{ID}-icon:` or uppercase-only `:{ID}:` by default, but perhaps the shortcode could be made customizable per project.
• I wish all issue type icons were made available as simply `:{type}:`, although this might lead to namespace conflicts especially for `:bug:` 🐛. 

PS: I originally tried to add this to the project JRACLOUD, but it wasn't available in the Create Issue dialog.