tchannel .call api change

gistfile1.py

# raw
response = yield tchannel.call(
    argscheme="raw",
    service="someservice",
    endpoint="something",
    body="RAWRESPONSE",
    headers={
        'X-Source': 'geo'   
    },
    ttl=1000
)

# json
response = yield tchannel.call(
    argscheme = "json"
    service="someservice",
    endpoint="maps",
    body="{
        'lat': 100,
        'lng': 140
    }",
    headers={
        'X-Source': 'geo'   
    },
    ttl=1000
)

# thrift
Foo = get_tchannel_thrift(FooThrift, 'fooservice')

response = yield tchannel.call(
    argscheme="thrift",
    "some_binary",
    headers={
        'X-Source': 'geo'   
    },
    ttl=1000
)
response = yield tchannel.call_thrift(
    Foo.getBar(Foo.BarResponse("hi")),
    headers={
        'X-Source': 'geo'   
    },
    timeout=5000
)
response = yield tchannel.as_thrift().call(
    Foo.getBar(Foo.BarResponse("hi")),
    headers={
        'X-Source': 'geo'   
    },
    timeout=5000
)
response = yield tchannel.thrift.call(
    Foo.getBar(Foo.BarResponse("hi")),
    headers={
        'X-Source': 'geo'   
    },
    timeout=5000
)

future = tchannel_sync.call(
    Foo.baz(True),
    headers={
        'X-Source': 'geo'   
    },
    ttl=1000
)

@blampe +1