Avoid implementing Crypto-Algorithms by yourself

[oli-h]

In package net.lingala.zip4j.crypto you implemented well known crypto-algprithms:

• PBKDF2
• AES

Both are offered out-of-the-box in JDK's javax.crypto library. Propose to use those as they are well tested and established - and potentially faster.

• The PBKDF-Stuff can be coded with only 10 lines of code
• The AES-stuff only requires ~11 lines of code