Split elc into elval and elgh, changed objfun

I want to calculate log f(y|uk)'s value at a separate time from the gradient and hessian (so that I don't have to store the gradient and hessian as long). To do this, I split elc into elval and elgh. Then I changed objfun and tests to use these new funcs.
started objfunc, only has log f(u) value so far
objfunc calcs value correctly
objfunc now calcultes imp sampling weights
objfun value calculation complete and correct.

started on 2nd loop in objfun to cal gradient and hessian
objfun now calculates gradient

neither gradient nor value are implemented in objfun.R yet
objfunc.c's hessian 1/3 done. "panda" coded correctly.

hessian split into 3 pieces s.t. hessian=panda+lobster +G t(G)
objfunc.c's hessian 2/3 complete. needs lobster.

so far calculates panda + G%*%t(G).
objfunc.c correctly and completely calcs hessian

next steps: implement objfunc in objfun.R, do tests
objfun.R now calls objfunc.c for loops

loops calculate weights, value, gradient, hessian