built lmp and aelmp functions and testcases

[hejun0524]

Things I have modified:

1. src/utils/

   • lmp.jl: get_lmp function
   • aelmp.jl: get_aelmp function

2. src/UnitCommitment.jl

   • registered get_lmp and get_aelmp defined above into the package

3. test/lmp/

   • lmp_test.jl: lmp testcase using 4 simple examples from the slides.
   • aelmp_test.jl: aelmp testcase using aelmp_simple

4. test/runtests.jl

   • registered the two pricing tests defined above

5. test/Project.toml

   • added Clp

6. Project.toml

   • added Clp

Also I think the .gitignore file ignores the .gz files, and I will send those test case input gz files separately. Please add them to the folder test/fixtures/