[web2py] Very minor bug in Version 1.91.6

[Matt]

Hi there,

A very small bug has crept into this version that means you can no
longer raise Service.JsonRpcExceptions without getting the following
error:

"TypeError: exceptions must be classes, instances or strings
(depreciated) not JsonRpcException"

This line (3487) in tools.py needs to be amended.

    class JsonRpcException(object):       <------- previously was
class JsonRpcException:
        def __init__(self,code,info):
            self.code,self.info = code,info

Thanks in advance,
Matt