Add weapon DPS stats

[richardthombs]

Basic weapon damage info is done now.

Still to do:

• Accumulate damage for items like the Rattler II which have sub-components that also do damage
• Accumulate the damage of all ship weapons into ship-wide totals for player and turret damage
• Surface the different firing modes of FPS weapons (currently only the first firing mode is listed)
• Surface mining laser energy output on the website