Enter these codes at the password screen:

 QUINCY         Guard perception secret
 MUFFIN         Guard size secret
 FATTY          Defiance secret
 DINO           Unlimited goodies
 FOXY           Top down mode
 BOSTON         First person mode
 FARLEYMYDOG    All secrets
 DEFAULTM       Default chapters
 GER1ENG5       All chapters

 Unknown so far:

 CORETIMES
 ALLTIMES
 JOE
 KAZ
 JASMINE
 DT
 SHOWTIME