Auto-focus main fields on page load

[rhaamo]

It would be great to auto-focus the main fields on some pages, for example:

• new part would focus the name input
• on add/withdrawn stock qty would focus Amount
• when adding a new stock the amount field would get focused probably too
  etc.

it would make things easiers and faster, just click + type a number and enter without having to switch to the mouse just to focus the field.