Fix pressure drop scaling

Previously was dividing instead of multiplying, now multiplies
Fix pressure drop scaling
Error Message

Program stops and gives error message if current is too high or too low
to attain required power.
Error message

detects if current is too high or too low
Error message

removed debugging message
Fixes

Fixed error messages to be consistent, changed baseline Li Organic model
conductivity to 10 mS/cm from 1 mS/cm
Fix jlow and jhigh boxes
Merge pull request #3 from AlasdairCrawford/master

Freeze fixes