Mark `package` as mutable global
Mark `package` as mutable global

Mutating `package.path` is common.

adan830/luacheck,adan830/luacheck,kidaa/luacheck,linuxmaniac/luacheck,xpol/luacheck,kidaa/luacheck,mpeterv/luacheck,xpol/luacheck,xpol/luacheck,mpeterv/luacheck,mpeterv/luacheck,linuxmaniac/luacheck,tst2005/luacheck,tst2005/luacheck