Keystore is reimplemented and it is mainly for storing
(key, value) pair generically. The certificate related
APIs are moved to the class CertTool instead.
Updates:
Provide the getInstance() which gives the singleton.
Fix the missing construction of the BIO in cert.c.
1. Have the new Keystore for mini-keystore impelemntation.
2. Add CertTool library and jni dll for handling keygen and certificates.
3. Make Reply hidden.
4. Revert some 'incorrect' change and correct the description.
