Jobs: Preference warn only for Profit and Loss transactions/accounts

[ASWatCR]

In the Preferences, there should be two options re warning if jobs are not assigned:

- Warn if Jobs are not assigned to Profit and Loss transactions

- Warn if Jobs are not assigned to all transactions

Its frustrating when if gives warnings and all the accounts are Balance Sheet items. 

Obviously some people may want to track this, hence the need for two options.

"Warning re assigning job codes to Balance Sheet accounts - unnecessary"