Implement password changing

[ElwooD07]

1. After changing a password all data in storage will be invalid bacause of key and iv changing. I need to implement some mechanizm for rewriting all data with new key and iv or mechanizm for key and iv wrapping with dynamically changed password.
2. I can change key and iv generation algorithm to more secure in the scope of this issue. Suggestion: continue to use SHA256 algorithm, but with 10.000+ iterations. Each iteration must be applied on hexademical representation of previous SHA256 result. Approach like this will increase the persistence to the bruteforce attack.