added and tested working showBookCopy() function
Merge branch 'master' of https://github.com/g2-aj/cs304 into branch_kris
changed the sql script a bit
Merge pull request #26 from g2-aj/branch_kris

I added create HasSubject table in populate_library_tables
Merge branch 'master' into branch_lin
Placed HoldRequest for Borrower
Merge pull request #27 from g2-aj/g3-ks

Placed HoldRequest for Borrower
Merge branch 'master' into branch_lin
Deleted system class
Merge pull request #29 from g2-aj/g3-ks

Deleted system class
Merge branch 'master' into branch_lin
Finished librarian function