plot temp and salt at stations locations

[MatthisAuger]

From issue https://github.com/PaulSpence/Denman2024Voyage/issues/23#issue-2382767804

Added a code (Station_Hovmuller.ipynb) that plots a 2-month Hovmuller of temperature or salt at the location of a station provided in Jo's file.

[PaulSpence]

awesome @MatthisAuger! can you post the plot here?

[MatthisAuger]

The parameters you can play with in the scripts are:

• _stationindex ; between 0 and 135.
• _variablename ; 'temp' or 'salt'.

I can make a more intuitive version later if that's useful

Here is example for station 50: