Books an insurance option on the specified reservation number.
Input
transtype - "BOOKINS"
login - API user's username
password - API user's password
resnumber - The reservation number for the reservation to which to add insurance
bookrequest - A BookRequest object (see also https://support.softrip.com/projects/kbase/wiki/JSON_API_-_BOOK and https://support.softrip.com/projects/kbase/wiki/JSON_API_-_GETRESINSOPTIONS)
bookcommands - An array of bookcommands (as returned by GETRESINSOPTIONS) of insurance services to book
Output
Reservation object - Same output/format as a GETRES response