#4232 import external calendar availability

[staysgt]

Changes

User's can import their availability from an external calendar by entering a .ics link in their scheduling settings. Then, when they go to fill out their availability, their external calendar business will show up on the availability filler outer. Added the node-ical dependency which is used for parsing the ics url.

Screenshots

getUserIcsBusyTimes with no ics url set

getUserIcsBusyTimes with ics url set

Schedule settings:

Availability filler outer with ics set:

Availability filler outer 'fill in from external calendar' button with no ics url set

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Closes #4232

[wavehassman]

amazing job!