Load Singleplayer DMX values

[ampreeT]

This forces the game to reload the weapon parameters on level initialization and to use singleplayer values in a cooperative map.

Fixes some issues in #144.

Notable Changes:

• Crowbar's attack speed is now same as singleplayer
• MP5 clip size now uses singleplayer values (45 to 30)
• Weapon damage values now matches singleplayer values

[Alienmario]

LGTM. Are there any prediction issues?

[ampreeT]

LGTM. Are there any prediction issues?

The only prediction issue that I have found is holding the reload button while the MP5's clip size is full at 30. The client still thinks that the MP5 clip size is still 45.