Tiny UI fix
Search for main authors of the book as well and not just from the hasAuthors table
Merge branch 'master' of github.com:Peggytastic/304Library
Was searching for mainSubject but that field does not exist in book table
Got rid of printlns
Got rid of other printlns
Minor fixes
borrower now needs to exist and have a valid account
Merge branch 'master' of github.com:Peggytastic/304Library
added function to return list of subjects, updated UI to let users select existing subjects when adding books or generating reports
Merge branch 'master' into dlee

Conflicts:
	src/ClerkTransactions.java