Fixed bug with error.data. It can be an object after decoding too.
From https://github.com/wikimart/jsonrpc/commit/28ed685de67a65111986ede465c1000b8cfd0a23
Posibility to set handler after constructor.
From https://github.com/dusty-playground/jsonrpc/commit/186591f19c2008ee6248478ec818bf0a5fcd0a98
Possibility to set or unchange the display_errors behavior.
See also https://github.com/matsubo/jsonrpc/commit/1c65e2c4985970a4e4a8083553bfa86969260c32