trial: Encrypt and decrypt timestamp

Add functions to encrypt and decrypt a timestamp. We'll be using those
functions to write the encrypted timestamp of the first trial launch
date to a file.

Decided to go for some light encryption instead of just storing a plain
or base64-encoded value. Still need to come up with a key, but that will
be stored as a plain string in the binary.

Need a way to capture the results so we don't end up panicking. Trouble
is, 'magic-crypt' doesn't implement the required `Error` traits, so I
can't just slot it into 'error-chain'. Still trying to work out how to
deal with that.

Also add a function to get the days remaining from now.

0 files changed, 0 insertions, 0 deletions