Added Gunslinger Class

[Azzzzzy]

Added Gunslinger Class
https://www.dandwiki.com/wiki/Gunslinger_(5e_Class)

[NickVendel]

I didn't sleep last night, so checked this file in half-asleep state, take comments with grain of salt (and there's also some stuff i probably missed... like the fact there's no links to the article within elements)

[NickVendel]

Some things from previous review weren't addressed. Also, after everything is solved, whole file still needs to have "url setters"

[Azzzzzy]

Still don't know how exactly to deal with

      <description>You can mark one enemy and gain advantage against it until you target another creature, the target drops to 0 HP or 1 minute passes.</description>
    </sheet>
    <rules>
      <stat name="sniper mark:uses" value="1" bonus="base" />
      <stat name="sniper mark:uses" value="wisdom:modifier" bonus="base" />
      <stat name="sniper mark:rest" value="Long Rest" />
      <stat name="sniper mark:rest" value="Rest" level="20" />
    </rules>

Edit: Found a way to fix it.