Request logger /service/logger/reasons with CORS rather than JSONP

[ansell]

Requests to logger.ala.org.au/service/logger/reasons using JSONP are not using caching, so they are prone to breaking when logger.ala.org.au is struggling. The fix is to rely on CORS and change JSONP requests that currently look like:

https://logger.ala.org.au/service/logger/reasons?callback=jQuery112401583792809409157_1539020441101&_=1539020441102

to simple JSON requests like:

https://logger.ala.org.au/service/logger/reasons

which is cached and is not as prone to disturbance when logger.ala.org.au is struggling.