add HV decorator
BUG: wrong super class
checks for scalar outputs
BUGS: small fixes, flatten grads and tuple/list mismatch
check for multiple outputs
numbers should be treated as arrays (they share methods?)
get_symbolic_arg => get_sym_arg
fix _vector arg handling
better cache_id based on dim; inherit for HV
BUG: deepcopy didn't work (defaults carried across) AND reversed defaults
update tests
minor updates
allow cache_id to be called without args
add l_bfgs_b minimizer
add fmin_cg to minimizers
clean up cg return vals
TST: add optimize tests
remove old files
add NCG minimizer
update context tests