Chain33 JAVA SDK release 1.0.8

增加以下接口，供外部调用

TransactionUtil.generatorPrivateKeyString() 创建私钥
TransactionUtil.getHexPubKeyFromPrivKey(私钥) 根据私钥获得公钥
TransactionUtil.genAddress(公钥) 根据公钥获取地址
TransactionUtil.validAddress(地址) 校验地址是否正确
StorageUtil.createOnlyNotaryStorage 创建内容存证模型(payload)
StorageUtil.createHashStorage 创建哈希存证模型(payload)
StorageUtil.createLinkNotaryStorage 创建链接存证模型(payload)
StorageUtil.createEncryptNotaryStorage 隐私存证模型型(payload)
StorageUtil.createEncryptShareNotaryStorage 创建分享隐私存证模型(payload)

Chain33 JAVA SDK release 1.0.7

Update the readme