Version 0.4.2

• Refactor impl of encryptor
• Clean some code

MMKV has been packaged as android aar lib and uploaded to the maven repository.
Import it in gradle directly like this:

dependencies {
    implementation("net.yangkx:mmkv:0.4.2")
    // Or another one with encryption feature
    // implementation("net.yangkx:mmkv-encrypt:0.4.2")
}

Crate address: https://crates.io/crates/mmkv

Full Changelog: 0.4.1...0.4.2