Typo fixes in readme, fix another h=.2 reference, reorder hamiltonian in exact code, add more tests

[toddytharmonkey]

• Typo fixes in readme, combed through with a spellchecker this time
• Bugfix: In kernel, found another reference to h=.2 for TFIM, changed this to h=1 for consistency with exact file
• Exact code hamiltonian reordering: Does not change how precalculated exact distribution is made, but now if using qiskit to make hamsim circuit with our hamiltonian functions, it will be made in the same order as our manually created hamsim circuits
• Also have seperated exact code hamiltonians into the notebook
• Added method =2 and method=3 test, and also a skipped test. Skipped test compares qiskit circuit to ours but failing right now due to some sort of inconsistency with 2Q gate angles