Update the UI for Import & Export Features

[Garywoo]

The UI for the import and export features were lacking the Salesforce Lightning Design System love 💔

I've updated both of these features to use this modern and standardised styling system, updating the look and feel of both of these areas, along with making some other minor usability tweaks.

Screenshots

Change Log

• Updated the UI of the Import & Export features to use the Salesforce Lightning Design System
  • Unified the Header.
  • Updated the loading spinner.
  • Relocated the help button to the header, in a familiar place for Salesforce users.

Export Feature

• Added icons to the autocomplete suggestions to visually denote data type, and to reveal relationships which can be expanded.
• Added confirmation dialogs when clearing the Query History or Saved Queries. No more accidentally losing your history.
• Bumped the number of recent queries in the Query History list from 20 to 100.
• Made autocomplete work after an uppercase FROM keyword - Fixes Keywords should be case insensitive on auto-complete #189
• Hitting the F5 key now also runs the export. Frequent users of SSMS and other database tools rejoice!
• Tweaked some of the UI text to clarify the functionality of some features.
• Moved the lesser-used saved query clearing buttons into an expandable menu.

Import Feature

• Added original source column names to the field mapping section to help you understand what data is going where.
• Updated the execute button to dynamically change its text depending on the action being executed. No more clicking Import to update some records.
• Updated the field types in the Configure Import and Field Mapping sections to use relevant types. Quickly clearing the field value is now possible, and useful when mapping fields or selecting an object.

[jefersonchaves]

This is awesome. How might we get this over the line?

[Astisme]

@sorenkrabbe can you please look into this? it's been open forever and only touches the UI. It would be a great improvement for this extension!

[jefersonchaves]

Hello @Astisme - I agree with you, in the meantime you should look into https://github.com/tprouvot/Salesforce-Inspector-reloaded which is being maintained and has many other features.

[Garywoo]

@jefersonchaves Oh cool, I wasn't aware this existed. I've been running my forked version for years now. I'll switch to using this instead since it includes my changes, plus some others I'd been meaning to implement myself! Hopefully I'll find some time to contribute to it in future.

[tprouvot]

@Garywoo your new contributions are more than welcomed !
Your UI improvements are very well appreciated from the community 👏

[Astisme]

And this summarizes why this PR should be merged.