Required changes for distrib package support, all remaining changes will be isolated to Random and DistribFunctionResolver classes.

Removed unused fields from LLVMModelData structure, added field for pointer to Random object.
Updated all the Resolver objects to take a ModelGeneratorContext instead of the fields from
the context. Code is smaller, and was needed by distrib as it needs access to the Random
object in the context.

Added distrib test file.

Stubbed out DistribFunctionResolver, correctly identifies distrib functions now.
add first distribution function, basic support for uniform distrib
copy Random to new models, fix bug in gcc std::uniform_random, fix bug in getting default seed
add testing file
add copy ctor to random to get system time, add test for microseconds
tweak tester for Windows
Removed RoadRunner::getEigenvalues and replaced with getFullEigenValues and
getReducedEigenValues which return the eigenvalues for the respective Jacobians.

Updated calling code. Resolves #65.
fixed bug in duplicating Random dist obj
removed divide by zero check, let it go through and return and inf
add support for normal distributions
tweaks for msvc
tweak testing files
Merge branch 'develop' into rate