Add User Availability to Qualifiers Context

[bzzz-coding]

Fixes #508

Changes

• Added availabilityTimeSlots to qualifiers context
• Implemented functionality to show and update availability from qualifiers/2 page
• Updated documentation in mkdocs, reflecting the current qualifiers JSON structure
• Disabled time zone dropdown UI and set time zone to Pacific Time/Los Angeles

Screenshot

Disabled Time Zone Selection

[bzzz-coding]

Changes haven't been merged because this issue has dependency--needing design team to finalize new designs for the qualifiers page.