chapter264, [SORA][SORA Network] SorachanCoin: Improvement security of SecureString.

Hello friends!
We will soon complete the verification of new features. (e.g. getblockqhash)
We would like to go with the release …..
But before that, we found one problem that have been from before SORA released.

In the process of the SecureString, we found a problem that the passphrase remains in “plain text” in the object before passing.
Therefore, we have improved the SecureString so that the “plain text” passphrase is cleaned by “::OpenSSL_cleanse” in the functor method.

allocator.h (class SecureString)

eg usage: SecureString functor.

eg usage: SecureString functor QString.