Add Sentence field to lib list output

[silvanocerza]

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Installed libraries' sentences are now shown in arduino-cli lib list output.

Now:

$ ./arduino-cli lib list
Name         Installed Available Location Sentence                                                                      
ArduinoJson  6.11.0    6.15.2    user     An efficient and elegant JSON library for Arduino.                            
AudioZero    1.1.1     -         user     Allows playing audio files from an SD card. For Arduino Zero and MKR1000 only.
Sodaq_HTS221 1.0.0     -         user     An Arduino library for the HTS221 sensor.                                     

Before:

$ ./arduino-cli lib list
Name         Installed Available Location
ArduinoJson  6.11.0    6.15.2    user
AudioZero    1.1.1     -         user
Sodaq_HTS221 1.0.0     -         user

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[cmaglie]

We don't have limit on the sentence length, I think we should cut if it's too long, for example on my installation I have:

so I see two problems:

1. sentences that are too long will stretch the width of the table too much, in this case I have a single library with a very long sentence and it will create a lot of "empty" space on all the other rows
2. the same thing happens when a long "version" appears in this case I have 1.15.0-ALPHA-precompiled that stretch the second and third column creating a lot of empty space

I think that both can be easily fixed:

1. Just cut the sentence if it is too long, I guess 40 chars is enough.
2. You can set different column width modes, in particular there is the table.Average mode that sets the column witdth to the average length of all the elements listed (and not the max of them), in your case you can set

t.SetColumnWidthMode(1, table.Average)
t.SetColumnWidthMode(2, table.Average)
t.SetColumnWidthMode(4, table.Average)

where column 1, 2 and 4 are the "Installed", "Available" and "Sentence" columns. Doing so will avoid that a single very long element will increase the width too much.

Finally I would change "Sentence" to "Description".