Review changes related to Components and WasteStream

[yalinli2]

Hey @joyxyz1994 , I made the updates as we discussed, can you have a look at the commit b47e36c and make updates as you see fit? I added doc and updated tests accordingly.

Note that commit didn't pass the test because I used functions (aliases) that haven't been released in the existing thermosteam, I reverted it in the next commit 8b61f59 and the all tests are passed now

Thank you!