Add plugin ClassParser

[Damir37]

Parsing class:

• Class name
• Magic value
• Class version
• Last modified
• Hash sum md5/sha1/sha256/sha512
• Constant Pool

[Konloch]

Hi, sorry about the delay! Thank you for your contribution! We've decided to include this as an external plugin - https://github.com/Konloch/bytecode-viewer/commit/62ade7c877c7482a6359a28bc50aeec13fe99b54