Jade moses cherrypick 28fe32e198 to 4f5ad2f9ee

Here are changes Jade did on her branch

https://github.com/jadeoneill/moses

I cherry picked the commits from

https://github.com/jadeoneill/moses/commit/28fe32e1980033408037d454c1068ea59f1f6fdf

to

https://github.com/jadeoneill/moses/commit/4f5ad2f9ee22221f1cd84c9ffdfafca28065ad7c

To sum up,

* cleaning the combo interpreter
* removing parts not used anymore by Embodiment
* add equ combo operator (==)
* define fold recursively in combo (using equa)
* make PLEASURE support the procedure repository