Those will make it possible to securely host 'kopia server' embedded
in a desktop app that runs in the background and can access UI.
- added support for using and generating TLS certificates
- added /api/v1/shutdown API to remotely trigger server shutdown
- added support for automatically shutting down server if no requests
arrive in certain amount of time
- added support for generating and printing random password to STDERR
TLS supports 3 modes:
1. serve TLS using externally-provided cert/key PEM files
2. generate & write PEM files, then serve TLS using them
3. generate and use emphemeral cert/key (prints SHA256 fingerprint)
Adding test to probe snapshot failure. Tests snapshot of non-existent source directory, and then iterates through file permissions for files, directories, and issues snapshot to the source. Permission combinations are applied to a parent directory of the source, source itself, contents of source root when the source is a directory, and contents of a subdirectory in that source root.
Fixing kopia executable panic when a directory's contents can't be read. Previously the only Lstat error responded to was not-exist, letting other errors fall through and passing a nil `os.FileInfo` to the following function call, resulting in panic.
