Error messages from calculations

[neoJINXD]

From the D2 presentation, the professor mentioned that we need more detailed error messages to let the user know the exact issue if a calculation fails. This issue whould also be handled and displayed on the UI.

Something I noticed later on, on the web version with node, the entire server shuts down when you get an error. Should catch and handles those properly.

[EmanuelUnity3D]

I completed a first pass on this. I added domain exceptions where applicable and removed all type exceptions so that they could be raised at the parser level. Moreover, I added some exception handling at the parser level so that an appropriate message is returned to the front-end whenever an exception is raised. The latter part could use some more work. Pyparsing exceptions (not composed by our code) are unintuitive to non-technical users and should be reworked.

[EmanuelUnity3D]

Also, we will need to add test units for these exceptions.

[cpotteck]

After a few PRs. user-facing error messages are much improved (including parsing errors, and mostly fit in the UI. User guide also gives some details on each one.

Still need to investigate the web version problem reported above and add tests covering all exceptions.