set version of C parasail library for build//install

[EricDeveaud]

Hello,

while installing parasail-python bindings, the installation download hard-coded 'https://github.com/jeffdaily/parasail/archive/master.zip'
wich is moving along the time.

this may be problematic, as installation of the same version of parasail-python bindings along the time, will install a different version of C parasail library.

this breaks some reproducibility rules.
I have no guaranty that I will be able to reproduce the same installation in a near future, or in other computer.

either set a fixed version of C parasail to be built with the python bindings, either provide an installation mechanism the allows to use external C libparasail

regards

Eric