added sample subjects
uncomented options category in sellbookpage.php
fix sell book in sellbook.php
Added generic error page
Merge branch 'andrew-secudev' of https://github.com/laronandrew11/animolibro into andrew-secudev
these files now redirect to the error page
Merge branch 'andrew-secudev' of https://github.com/laronandrew11/animolibro

Conflicts:
	sql_scripts/RUN THIS TO SET UP DB/consolidated_insert.sql
Contact Number = BIGINT; Password Hash = LONGTEXT
Use SHA256 to hash password
Merge branch 'andrew-secudev' of https://github.com/laronandrew11/animolibro
modify sql script, password and contact# length
Error page
Merge branch 'andrew-secudev' of https://github.com/laronandrew11/animolibro into andrew-secudev
fixed errors in sql script
Merge branch 'andrew-secudev' of https://github.com/laronandrew11/animolibro into andrew-secudev
basically the same
Added authenticator file to keep anonymous users out of members-only areas
Merge branch 'andrew-secudev' of https://github.com/laronandrew11/animolibro into andrew-secudev
will only show up if authenticated
"Authenticator" now working to keep unlogged-in users out of webpages for logged-in users