using binary search for _getExtentForRange in Time.js
CachedNcWMS async

 * CachedNcWMS was merged with NcWMS, since NcWMS was not used
 * CachedNcWMS is totally asynchronous (also handling dates)
 * Progress bar shows status also of date parsing
fixed tests and got rid of NcWMS.js
merged tests of NcWMS into CachedNcWMS
reordered functions in CachedNcWMS.js
added a couple of tests for CachedNcWMS async behaviour
slightly more efficient large array handling - avoiding copy
change variable name in CachedNcWMS to be more coherent
modified setTimeout call to work with jasmine local tests
removed comment from test and put stuff in runs() block
renamed CachedNcWMS to NcWMS
Merge pull request #240 from aodn/date_process

Async date process