make the colour bars for the contours and the map user defined

[jgriesfeller]

Is your feature request related to a problem? Please describe.
The clour scales are right now defined globally here:

pyaerocom/pyaerocom/aeroval/glob_defaults.py

Lines 2 to 10 in 26df81b

	var_ranges_defaults = {
	"default": {"scale": [0, 1.25, 2.5, 3.75, 5, 6.25, 7.5, 8.75, 10], "colmap": "coolwarm"},
	"ang4487aer": {
	"scale": [0, 0.25, 0.5, 0.75, 1, 1.25, 1.5, 1.75, 2],
	"colmap": "coolwarm",
	},
	"od550aer": {
	"scale": [0, 0.05, 0.1, 0.15, 0.20, 0.25, 0.30, 0.35, 0.40],
	"colmap": "coolwarm",

Different users have different priorities for how the scaling should look like. The scales should therefore be easily changeable (e.g. via the aeroval config file)

Describe the solution you would like to see
make the scales an optional part of the aeroval config file

Additional context
color bars are used at the contours:

The same values are also used here:

[heikoklein]

In addition, default color-maps should be defined by frequency, i.e. a range of 0-80 of hourly PM is fine, while it should be rather 0-35 for daily averages and 0-20 (or even less) for yearly averages.

[heikoklein]

In addition, default color-maps should be defined by frequency, i.e. a range of 0-80 of hourly PM is fine, while it should be rather 0-35 for daily averages and 0-20 (or even less) for yearly averages.

moved to issue #1258