__getattr__ was overriden in order to be able to call the script
using its reference (not prefixed by script_) from another workflow
script (see testTradeReports for example)

the problem is that it was doing a lot of useless getattr (each time,
it was checking for script_foo, even if foo is a transition, state, ...)

we now just change the context given to the script by adding foo
for script_foo to the context dict