More hashcat tests, Argon2 hash support and some cleaning

[amadejpapez]

• Previously the test, that was testing if every hashcat mode had a test, skipped modes that were no longer supported in the latest hashcat version (we have a description that that mode is only supported in hashcat legacy). I have removed that restriction and added around 10 new tests for them, so now we are really testing every hashcat mode we have.
• added support for all 3 variants of Argon2 (Add Argon2 hash #102)
• went through all of the files, cleaned imports, fixed some of the typos in comments and some other things
• I have also removed file first.cast from /images as it probably mistakenly came through when gifs were added