Add ArcGis ImageServer support

[nf-s]

Add ArcGis ImageServer support

Fixes #1458

Todo

• Support tiled endpoints (similar to MapServer)
• Look into multi-dim
• Look into raster functions
• Look into color maps
• Get feature picking working
• Test time-enabled ImageServer
• Remove selectable dimensions and multi-dim/raster function/color map fns
• Test token-based auth
• Integrate with ArcGis REST...
• Write unit tests

Test me

Test links

• https://www.lmbc.nsw.gov.au/arcgis/rest/services/NVR/SensitiveRegulatedLand/ImageServer
• https://spatial-img.information.qld.gov.au/arcgis/rest/services/Basemaps/LatestSatelliteWOS_AllUsers/ImageServer
• https://sampleserver6.arcgisonline.com/arcgis/rest/services/CharlotteLAS/ImageServer
• (Time enabled + multi-dim) https://image.wsapi.cloud.bom.gov.au/arcgis/rest/services/awra_historical/physical_day_crf_multivariable_archive_1985_2004_data/ImageServer
• (Time enabled + multi-dim) https://arcgis.asdc.larc.nasa.gov/server/rest/services/POWER/power_901_annual_meterology_utc/ImageServer
• (Tiled) https://imagery.oregonexplorer.info/arcgis/rest/services/OSIP_2022/OSIP_2022_WM/ImageServer

Checklist

• There are unit tests to verify my changes are correct or unit tests aren't applicable (if so, write quick reason why unit tests don't exist)
• I've updated relevant documentation in doc/.
• I've updated CHANGES.md with what I changed.
• I've provided instructions in the PR description on how to test this PR.