configurable toast duration

[comhar]

This PR implements the following:

• increase the default toast duration to 10 seconds
• add a duration param to setup_toasts
• add an x icon, that allows the user to close the toast

---

name: Configurable Toast Duration
about: Make the toast duration configurable + add an x icon that users can click to close the toast.
title: '[PR] '
labels: 'enhancement'
assignees: ''

---

Related Issue
#586

Proposed Changes
#586
tldr: this pr makes the duration of the toast configurable and increases the default duration from 3 seconds => 10 seconds. an x icon has also been added that allows the user to close the toast.

Types of changes
What types of changes does your code introduce? Put an x in all the boxes that apply:

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist
Go over all the following points, and put an x in all the boxes that apply:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.
• I am aware that this is an nbdev project, and I have edited, cleaned, and synced the source notebooks instead of editing .py or .md files directly.

Additional Information
Here's the new icon for each toast type.

[gitnotebooks]

Found 1 changed notebook. Review the changes at https://app.gitnotebooks.com/AnswerDotAI/fasthtml/pull/587

[jph00]

Nice! If you have a moment, perhaps do a followup PR to replace the string format with python 2 % format, so you can then remove all the doubled braces?