tests(nra): add testcases to resolve #54

[skip ci]
fix(heuristic): avoid backtracking in heuristic unless required

fix(style)

fix(heuristic): avoid backtracking in heuristic unless required

fix(style)
feat(heuristics): checkpoint on implementing ode simulation

feat(heuristics): checkpoint on implementing ode simulation

feat(heuristics): checkpoint on implementing ode simulation

feat(heuristics): checkpoint on implementing ode simulation

feat(heuristics): checkpoint on implementing ode simulation

feat(heuristics): checkpoint on implementing ode simulation

feat(heuristics): checkpoint on implementing ode simulation

feat(heuristics): checkpoint on implementing ode simulation

feat(heuristics): checkpoint on implementing ode simulation

feat(heuristics): checkpoint on implementing ode simulation
fix(heuristic): avoid backtracking in heuristic unless required
fix(style)
feat(heuristics): checkpoint on implementing ode simulation

feat(heuristics): checkpoint on implementing ode simulation

feat(heuristics): checkpoint on implementing ode simulation

feat(heuristics): checkpoint on implementing ode simulation

feat(heuristics): checkpoint on implementing ode simulation

feat(heuristics): checkpoint on implementing ode simulation

feat(heuristics): checkpoint on implementing ode simulation

feat(heuristic): ode sim heuristic

cleanup
fix(ode_solver): fixed bug in capd formulation that involve double negative --
fix(ode_solver): fixed bug in capd formulation that involve double negative --