upgrade javassist to 3.30.2-GA

[binfeiruci]

#622

[skybber]

Thank you, I still need to test whether you have included our modifications to the original Javassist.

[skybber]

Unfortunately, I had to roll back your changes because they did not include the Javassist modifications used by HotswapAgent. The fix should correctly consist of two commits:

• Commit (1): The new version of Javassist without any modifications.
• Commit (2): Changes related solely to HotswapAgent.

[binfeiruci]

oops, I forgot to check the changes.