Add image chart functions

[giswqs]

This PR adds more charting functions to the chart module.

Reference: https://developers.google.com/earth-engine/guides/charts_image

chart.image_byRegion

ecoregions = ee.FeatureCollection('projects/google/charts_feature_example')
normClim = ee.ImageCollection('OREGONSTATE/PRISM/Norm81m').toBands().select('[0-9][0-9]_tmean')
labels = list(calendar.month_abbr)[1:] # a list of month labels, e.g. ['Jan', 'Feb', ...]

chart.image_byRegion(
    image=normClim, 
    regions=ecoregions, 
    reducer="mean", 
    scale=500, 
    xProperty='label', 
    xlabel='Ecoregion',
    ylabel='Temperature',
    labels=labels,
    # colors=['red', 'green', 'blue'],
    )

[github-actions]

🚀 Deployed on https://65ce9991f900a14b99f7a66d--opengeos.netlify.app

[giswqs]

chart.image_byClass

Reference: https://developers.google.com/earth-engine/guides/charts_image#uichartimagebyclass

bqplot example with line smoothing

import numpy as np
import bqplot.pyplot as plt

fig = plt.figure(title="Random Walks")
x = np.arange(100)
# three random walks
y = np.random.randn(3, 100).cumsum(axis=1)

lines = plt.plot(
    x, y,
    labels=["Line1", "Line2", "Line 3"],
    display_legend=True
)

# Plot the lines with interpolation
line1 = plt.plot(x, y[0], 'b-', label='Line 1', interpolation='basis')
line2 = plt.plot(x, y[1], 'r-', label='Line 2', interpolation='step-after')
line3 = plt.plot(x, y[2], 'g-', label='Line 3', interpolation='cardinal')

plt.show()

[jdbcode]

Hi @giswqs, just a quick note to say I see the review request and will follow up shortly.

[giswqs]

No rush. I will be adding more commit over the next few days.

[jdbcode]

It looks like you're maybe still working on chart.image_byClass?
I saw the new Image_byClass class but the image_byClass function is unchanged from todo. Do you want to add it to this PR, or would you like to merge the current changes?

[giswqs]

@jdbcode Thanks fort testing it. I will be adding more classes and functions. Don't merge this PR yet.

[jdbcode]

Sounds good

[smith-kyle]

I'm a little late to the party, but I noticed you all aren't using a notebook review tool and wanted to invite you to review this pull request with GitNotebooks: https://gitnotebooks.com/gee-community/geemap/pull/1855

It lets you do things like comment on rendered markdown and code cells, so might be an easy win for your PR reviews.