New arch

[ThimotheeV]

This PR present the new architecture for the package. It seems to not have changed the previous pipeline.

model <- tp_compile("crbd", "smc-apf", particles = 5000)\
data_path <- tp_data("crbd")\
output_list <- tp_run(model, data_path, sweeps = 4)

More detailed model is now a RefObject (a modifiable object that can't be copied but which is always passed by reference). This object contains the following fields:

exe_list : Map (Set Option) Executable -- Mutable, but is just an optimization to not have to recompile so often
path : String -- Path to model source code
default_options : Dict -- Defaults options for this model

Based on PR 9, PR it corrected and expend.

To see what still need to be improved see TODO on the wiki

This is a draft because this PR needs a new compatible self-contained tpplc to work.

[maribraga]

Waiting for the new self-contained tpplc version.