Updated Quick-Registration Grid handles uncommitted state/save interactions like a spreadsheet

### Concern and Goal:
The current implementation has to ask the user if they want to keep or change their un committed work any time they change focus. This is not familar to anyone who has used Google Sheets or similar. The app needs to allow users to switch focus between fields and rows, add/remove rows, and update values until they are finally committed via Save.
A value entered via Search needs to look different than one that has been manually entered or modified

### Specifics:
1. A row that is enrolling an existing student appears with colors inverted (white on dark grey)
2. Clicking/tapping on a field with a search result highlights the entire value. Changing anything or typing when it is in this state deletes the entire value and all other value (e.g. middle and last names)
3. A searched value removed in this way must be searched again to recover
4. A new value can be edited or deleted, before it is committed, without affecting other values in the same row/record (e.g. first name could be changed multiple times and last name will remain unchanged)
5. After records are saved they appear in the history with their enrollment

### Choose Region Once. Group by Program Site. Reduce need to select TeamSeason with each record
6. Users submit records for a single region, thus the grouping for efficiency should allow for the user to select the region at the top of the flow.
7. Program Site is the expected grouping. Selecting this, then TeamSeason makes both values the default each time the user adds a row/record
8. User can change the duplicated team and it will continue as the default
9. User can change the duplicated Program Site, which will clear the selected TeamSeason
10. Once a student assignment (Site+TeamSeason) is completed it can be saved and this becomes the new defaullt

### Additional Requirements:
- A spreadsheet component will make UX more understandable. Records that have been saved could be copied but cannot be re-saved/modified
- Implement this [react-datasheet-grid](https://github.com/nick-keller/react-datasheet-grid/tree/master) or an equivalent