fixed #213

processDates function took too long to process as it might have had close to 20,000 items sometimes.

The solution was to run this function in an async closure in a chunked way, letting the browser take control every 1024 items (can be easily changed). The result is slightly slower processing time, but also getting rid of the annoying popup saying a js script took too long to run
removed console.log
Merge pull request #237 from aodn/issue-213

fixed #213