Working and tested

modified:   .gitignore

modified:   Project.toml DiffEqBase, RecursiveArrayTools, Unitfu only
modified:   README.md    Short explanation
modified:   src/MechGlueDiffEqBase.jl Drop experiments, norm only.
deleted:    test/Manifest.toml
deleted:    test/Project.toml
modified:   test/runtests.jl  Include 1..3
new file:   test/test_1.jl    First version
new file:   test/test_2.jl    First version
new file:   test/test_3.jl    First version