Review of the past two weeks

In the last two weeks, my work can be summarized as two parts: wrapping up the final pull request and done the benchmarking for BoundaryValueDiffEq.jl.

The BoundaryValueDiffEq.jl splitting work is finally done, past two weeks mainly focused on some extra trivial works on ensuring the parent packages and subpackages are using the correct packages and the file paths are not using relative paths afterwards.
Finally the BVDAE solvers PR was merged 🎉🎉🎉🎉🎉!. What’s left to continue polishing in this work is to standardize the interface and refactor the internal of Ascher solver, some future work will be tracked in this isue: Some issues with BVDAE solvers in BoundaryValueDiffEq.jl, mainly about finding more tests cases (over-constraints and under constraints BVDAEs) to prove its reliabilities, reduce the memory allocations and overhead etc.
Rerefactored the previous work on MIRKN methods for SecondOrderBVProblem, and the convergence tests are passing now for the implemented MIRKN4 and MIRKN6 methods, but when I was constructing a second order BVP, the interface of SecondOrderBVProblem did not accept 5 arguments analytical solution specified, I need to make the changes for alowing this.

More TODOs:

Refactor the implemented solvers to be compatible with the SciML style, and simplify the internal of Ascher DAE solvers.
Finish the MIRKN PR and get this PR merged as soon as possible!