* Removed libquazip-headers from trusty ci images
Trusty does not provide libquazip-headers (they are part of
libquazip-dev most likely)
* Bump rebuild counter
* Add source folder keeshare for sharing with corresponding define WITH_XC_KEESHARE
* Move common crypto parts to src/crypto/ssh
* Extended OpenSSHKey
* Move filewatching to own file (currently in two related classes DelayedFileWatcher and BulkFileWatcher)
* Small improvements for style and code in several classes
* Sharing is secured using RSA-Keys which are generated on demand
* Publisher signs the container using their private key
* Client can verify the signed container and choose to decline an import,
import only once or trust the publisher and automatically import all
data of this source henceforth
* Integration of settings into Group-Settings, Database-Settings and Application-Settings
* Introduced dependency QuaZip as dependency to allow combined export of
key container and the (custom format) certificate
Note: This implementation is not yet connected to the
database itself and will corrupt existing kdbx3 db's.
* Implemented memory and parallelism parameters for Argon2Kdf
* Using libargon2; libsodium does not support Argon2d algorithm
* Moved basic rounds parameter into Kdf class
* Reimplemented benchmark algorithm; previous was utterly broken
