New plugin "enc"

[mehdid]

A plugin to show, edit and create encrypted files using configurable methods to get the encryption key and encrypt/decrypt files. Basic operations :

• clara enc show [file]
• clara enc edit [file]
• clara enc create [file]
• clara enc encode [file](with possibility of taking source from stdin and/or output on stdout)
• clara env decode [file](with possibility of taking source from stdin and/or output on stdout) It is not necessary to implement many enc methods to start but only the one we are using currently.

[ana]

Done in commits:

https://github.com/edf-hpc/clara/commit/9c4c23b93293ee8ab72b35b3665a5202456898ac

https://github.com/edf-hpc/clara/commit/f9b2ccf6853528f5604305a32b73b50b12512090

https://github.com/edf-hpc/clara/commit/6e38136d5e6b74269fffcf566844da3af47894e2

https://github.com/edf-hpc/clara/commit/d2ba919540099be2fb1ec1f8b39d5a54a5795ef1