XWIKI-9782: New Crypto Service API

Work in progress, currently introduce support for:
 - common crypto types (keys, generation parameters, cipher parameters, ...)
 - string encoding (base64, hex, ...)
 - digests (MD5, SHA-1, SHA-224, ...)
 - symmetric CBC chained padded ciphers (AES, Blowfish, Cast, DES, RC2, ...)
 - asymmetric cipher (RSA)
 - key derivation functions (PKCS5S2, Scrypt, ...)
 - password based cyphers (using PBES2)

 Truncated history, see platform for more....
XWIKI-9782: New Crypto Service API

Fix dependencies.
XWIKI-9782: New Crypto Service API

Fix dependencies and versions.
XWIKI-9782: New Crypto Service API

Fix a badly named classes
XWIKI-9782: New Crypto Service API

- Minor refactoring.
- Allow usage of String for passwords
XWIKI-9782: New Crypto Service API

- Remove unsupported asymmetric key algorithm
XWIKI-9782: New Crypto Service API

- Fix a typo
XWIKI-9782: New Crypto Service API

- Fix wrong test package
XWIKI-9782: New Crypto Service API

- Add private key encryptor for easy management of private key encryption and decryption using password based ciphers.
- Improve PBES2 parameters to support custom random source
- Improve KeyWithIVParameters to better support custom random source
XWIKI-9782: New Crypto Service API

Typo
XWIKI-9782: New Crypto Service API

- Properly reset digest as documented in comments
XWIKI-9782: New Crypto Service API

- Add an internal bouncy castle interface for digest
XWIKI-9782: New Crypto Service API

- Fix checkstyle
XWIKI-9782: New Crypto Service API

 - minor test improvement
XWIKI-9782: New Crypto Service API

- new signer module
XWIKI-9782: New Crypto Service API

- update the pom to include the new module
XWIKI-9782: New Crypto Service API

- Fix test coverage precision
XCOMMONS-522: Upgrade Maven License plugin to version 2.6
+ fixed all pom.xml license headers which for some reasons were not noticed with previous version of the license plugin (maybe a bug that has been fixed)
[maven-release-plugin] prepare branch stable-5.4.x
[maven-release-plugin] prepare for next development iteration