Ability to select add-ons

[knstvk]

Add a "Select add-ons" step before the "Select project location" step.
It should show the list of add-ons (as checkboxes) available for this Jmix version, with the ability to filter by add-on's name and description.

[Fedoseew]

@knstvk you can check.

[knstvk]

Looks good, but let's simplify a bit:

• remove "Included in template" section at all, it's not editable and rather confusing
• remove the duplicated add-on name in brackets