Derive points example in ReadMe incorrect ?

[alex-s-gardner]

I think there is a SpaceLiDAR.points call missing in the Derive points example in the readme:

Derive points

using DataFrames
fn = "GEDI02_A_2019242104318_O04046_01_T02343_02_003_02_V002.h5"
g = SpaceLiDAR.granule(fn)
df = DataFrame(g)
149680×15 DataFrame
    Row │ longitude  latitude  height    height_error  datetime                 intensity  sensitivity  surface  quality  nmo ⋯
        │ Float64    Float64   Float32   Float32       DateTime                 Float32    Float32      Bool     Bool     UIn ⋯
────────┼──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
      1 │   153.855  -47.2772  -13.3536      0.307976  2019-08-30T10:48:21.047   393.969   -0.0671094      true    false      ⋯
      2 │   153.855  -47.2769  -11.2522      0.307978  2019-08-30T10:48:21.055   797.26     0.533529       true     true
      3 │   153.856  -47.2767  -13.775       0.307981  2019-08-30T10:48:21.063  1010.39     0.695938       true     true
      4 │   153.857  -47.2765  -11.729       0.307983  2019-08-30T10:48:21.071   852.614    0.544849       true     true
      5 │   153.857  -47.2763  -13.2443      0.307985  2019-08-30T10:48:21.080   980.66     0.620767       true     true      ⋯
      6 │   153.858  -47.2761  -12.1813      0.307987  2019-08-30T10:48:21.088   937.441    0.620531       true     true
      7 │   153.859  -47.2758  -11.9011      0.30799   2019-08-30T10:48:21.096  1235.02     0.73815        true     true
      8 │   153.859  -47.2756  -12.3796      0.307992  2019-08-30T10:48:21.104   854.127    0.545655       true     true

[evetion]

We could add it to the README, but as you might've noticed in #77, Granules implement the Tables interface by calling points themselves. So DataFrame(g) works, but if you need arguments (extent, etc), you need to specify it points.

I liked the shorthand, but it might be confusing. Might need to remove/deprecate it when we get to a stage where you can specify the fields you want.