Move sawed-off shotgun from Armory to Guns

[T-rexsuper1]

Additions

Adds sawed-off shotgun from CE armory into CE guns.

Changes

Changed preview to incorporate the sawed-off, changed readme to incorporate the sawed-off, added sawed-off sprite, added sawed-off code.

References

Same as recent SKS and Mini-14 movement.

Reasoning

SKS and mini-14 being moved into Guns from Armory inspired me to make this PR. Sawed-off fills a niche that no other weapon really fills, it is not worthy of being thrown in into other bloaty stuff from Armory. Perfectly fine addition to Guns in my opinion

Alternatives

Could add a non sawed-off double barrel shotgun to Armory. Could also just not add sawed-off into Guns at all and instead use the governor, even though it's an entirely different weapon.

Testing

Check tests you have performed:

• Compiles without warnings
• Game runs without errors
• (For compatibility patches) ...with and without patched mod loaded
• Playtested a colony (specify how long)

[T-rexsuper1]

Willing to make the PR to Armory, removing the sawn-off, if this gets approved.

[Safairette]

Not the biggest fan of this change in a vacuum, mainly because we already have a smaller sidearm shotgun alternative via the Governor and having both feels somewhat redundant in Guns.

[T-rexsuper1]

Not the biggest fan of this change in a vacuum, mainly because we already have a smaller sidearm shotgun alternative via the Governor and having both feels somewhat redundant in Guns.

Governor and sawed-off are entirely different weapons, practically incomparable. It's not reduntant at all, since 410 is wayyyy less powerful than 12 gauge and having a full power 12 gauge pocket option is really interesting gameplay wise both for raiders and players