Better descriptions for all default weapons

This also includes some simple stats. The calculation formulas I used:
Rate of fire (in rounds per minute) = 70/Lock*60
Lifespan (in seconds) = Range/70
Add weapon descriptions for funwithguns.cdogscpn

This also includes some simple stats. The calculation formulas I used:
Rate of fire (in rounds per minute) = 70/Lock*60
Lifespan (in seconds) = Range/70
Merge pull request #331 from Wuzzy2/gundesc

Improve and add weapon descriptions