Hashed passwords, more exp, other small changes

Passwords are now salted and MD5 hashed before being stored.  Although
it is not the strongest way to store the passwords, it is better than
plaintext.

I increased the chance for boss monsters to spawn.  Since these are
worth more exp than regular monsters, it will help players level up
faster.  I also increased the overall experience multiplier.

I removed night time completely.  Having all the lights turn off in the
middle of a map gets very annoying.

I removed the spam message that occurs when a player reaches level 250
in a class.

I removed exp loss on death.  This remedies the situation in which it
was hard for squishy high level players to level up.

I increased the effectiveness of ammo regen.  Players will now be able
to spam whatever weapon they want.