update docs
imported libSBML 5.10 src tree
add test model
added JIT compiler info to Compiler interface / version string
update cmake to work with LLVM 3.4, use c++ sstream for str cat
change exception to warning for NaN values
updates to compile with LLVM 3.5
tweaks to compile with LLVM 3.1
removed pointless functions, implement virtuals in C backend
fixed arg parsing bug in simulate, bumped version
add benchmarking files
updated NEWS