fixed a hash calculation issue.

small fix

layering issue fix

- adjusted price 2500 > 3700
- updated description to include specs

A silent mode feature has been added!
-players can now switch the sub into silent mode.
-added buttons for this to both the command and engine rooms.
-silent mode will disable the reactor and switch to battery power.
-only the main ballast, engine and navigation will be powered.
-engine top speeds will be reduced to 30% to reduce noise.
-bear in mind that O2 will be disabled while running silent mode

description correction

Initial upload