not playing dangerous games with setLayerIndex

using setZIndex on drawing layers so order doesn't get messed up
Fix for #1138 - allow download given a URL list.
Refactor, removing duplication etc.
Merge pull request #1152 from aodn/issue_1138

Issue 1138
Email address is passed correctly into aodaacJob
Merge pull request #1154 from aodn/aodaac_email_vit

Email address is passed correctly into aodaacJob
#546 - Remove operation combo/always display from and to date when subsetting non-gridded layers.
Provide reset option to reset from and to date back to min/max as applicable if a date has been entered.
Make display of gridded/non-gridded date range selection more consistent.
Merge pull request #1150 from aodn/issue_1134

not playing dangerous games with setLayerIndex
Merge pull request #1155 from aodn/issue-546

#546 - Remove operation combo/always display from and to date when subse...
Merge master. Fix massive conflicts
Merge master. Fix massive conflicts
Merge tests after merge master conflicts
Merge tests after merge master conflicts