Undocumented compilation error using params as param name in rpc method definition

[jangko]

The following rpc method definition using params as the param name will trigger compilation error. If renamed to something else it will be ok. looks like the internal templates and macros are messing with it because they use params as their working variable. If we cannot fix it, then doc it at least.

server.rpc("method1") do(params: string) -> bool:
   return true

Error message:

...\engine_api.nim(83, 9) template/generic instantiation of `rpc` from here
...\json_rpc\server.nim(19, 16) template/generic instantiation of `rpc` from here
...\json_rpc\router.nim(155, 73) template/generic instantiation of `async` from here
...\json_rpc\jsonmarshal.nim(244, 22) Error: undeclared field: 'elems' for type system.string [declared in F:\projects\status-nim\lib\system.nim(34, 3)]