[UX] Further Improvements

[brxken128]

This implements the changes specified in #204.

A lot of print statements have been removed, and I feel as though I prefer it this way as it matches other command-line applications.

Most command-line applications don't print to the console unless they've errored, and I feel that's a good thing to stick by.

Obviously this is very subjective, so feel free to object :)

[brxken128]

@pleshevskiy I removed the Deoxys feature. The feature was probably a bad idea as it needed to be enabled in order to decrypt files that were encrypted with Deoxys.

I'm still not going to add the support to encrypt with it (although I will do some testing to see how performance is doing), but we still need to provide the option to decrypt with it.

I also removed the visual feature by default, as this should clean CLI output up a lot as well. My goal is to make Dexios more UNIX-like, and only alert the user to something where it's required.

[pleshevskiy]

LGTM!