This looks like a log but it's just moving the code that lived in
cmd/gm/ui.go into it's own pkg that makes it clearer where each part of
the UI lives.
I am also adding the functionality for bulk sprint demo to grab names
from github usernames.
- **Adding sprint command to view items in current sprint and warning
when limit is too small**
- **Adding select / deselect all and demo output**
- **Added hotkey 's' to select all subissues along with the issue
selected**
Example of how I generated the demo docs for mdm this sprint
```
./gm sprint mdm --limit 200
'pressed l to select all issues'
'pressed w to select a workflow'
selected Bulk Demo workflow and hit enter
copy/paste features to features and bugs to bugs
modify gh usernames to @email and hit 'space' after every ) in the markdown to get it to trigger
hit tab for all issues listed under each user
...
profit
```
