Add lb and ub for BVProblem

Author: ErikQQY

src/problems/bvp_problems.jl

@@ -113,19 +113,21 @@ every solve call.
   doesn't store array size as part of type information. If we can't reliably infer this,
   we set it to `Nothing`. Downstreams solvers must be setup to deal with this case.
 """
-struct BVProblem{uType, tType, isinplace, nlls, P, F, LC, UC, PT, K} <:
+struct BVProblem{uType, tType, isinplace, nlls, P, F, LB, UB, LC, UC, PT, K} <:
        AbstractBVProblem{uType, tType, isinplace, nlls}
     f::F
     u0::uType
     tspan::tType
     p::P
+    lb::LB
+    ub::UB
     lcons::LC
     ucons::UC
     problem_type::PT
     kwargs::K
 
     @add_kwonly function BVProblem{iip}(f::AbstractBVPFunction{iip, TP}, u0, tspan,
-            p = NullParameters(); lcons = nothing, ucons = nothing, problem_type = nothing, nlls = nothing,
+            p = NullParameters(); lb = nothing, ub = nothing, lcons = nothing, ucons = nothing, problem_type = nothing, nlls = nothing,
             kwargs...) where {iip, TP}
         _u0 = prepare_initial_state(u0)
         _tspan = promote_tspan(tspan)
@@ -175,9 +177,9 @@ struct BVProblem{uType, tType, isinplace, nlls, P, F, LC, UC, PT, K} <:
         end
 
         return new{typeof(_u0), typeof(_tspan), iip, _nlls, typeof(p),
-            typeof(f), typeof(lcons), typeof(ucons),
+            typeof(f), typeof(lb), typeof(ub), typeof(lcons), typeof(ucons),
             typeof(problem_type), typeof(kwargs)}(
-            f, _u0, _tspan, p, lcons, ucons, problem_type, kwargs)
+            f, _u0, _tspan, p, lb, ub, lcons, ucons, problem_type, kwargs)
     end
 
     function BVProblem{iip}(f, bc, u0, tspan, p = NullParameters(); kwargs...) where {iip}