135 cablenml improvements (#136)

# CABLE

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## Description

The cable.nml documentation can be improved.

- Many entries in the description table do not actually have default
values.
- Some default values are wrong. Eg. vegparmnew = .FALSE.
- Some namelist variables are missing.
- Why is the default restart_in = ' ' ? What does it mean?
- The table widths could be adjusted.
- It looks like filename%veg and filename%soil are not used.

Fixes #135

## Type of change

Please delete options that are not relevant.

- [x] New or updated documentation

## Checklist

- [x] The new content is accessible and located in the appropriate
section.
- [x] I have checked that links are valid and point to the intended
content.
- [x] I have checked my code/text and corrected any misspellings