Standard library linters

[SquidDev]

Just some ideas for linters which pick up on potential issues with people using standard library functions:

• Suggest replacing pcall(function() return f() end) (or pcall(function f() end) with pcall(f). This should probably only be done if all arguments are pure/will not error.
• Check format strings (string.format and ("foo"):format) have the correct number of arguments. And possibly that the strings are well-formed.
• Check Lua patterns are welformed within the various string.* functions.

[magiczocker10]

string.xx will be replaced with :xx (except of string.dump) could be a default option that can be disabled in the config.