Switch to BoltDB

The user database has been changed to BoltDB. Config keys should also be changed, for the old LevelDB path use ldb_database_path, for the new BoltDB file path use bdb_database_path. To convert the database to BoltDB run ns2query --convert after changing the config. LevelDB isn't used anywhere now except for the conversion and will be dropped in next releases.

Fixed build date layout

Build date is now formatted properly as day.month.year.

Restart on IP change, better error messages

When the bot runs on embedded hardware (like routers) and the IP changes all connections (including UDP even though it's connectionless) stop working because source IP doesn't exist anymore. It's not an issue if the IP is static but in my case it changes on every reconnect on the ppp0 interface. When UDP write (send) results in an error the bot now restarts itself. It's easier and more robust than messing with every small network client running independently.

TLS handshake timeout increased to 2 minutes, on slow hardware the intitial crypto setup can take more than the default 10 seconds.

Some startup error messages are annotated now so it's easier to figure out what exactly went wrong.

Reconnects

In case of initial Discord connection failure, reconnect after a second. Also small database API refactoring in regard of path (prefix) building.

DB refactoring

Changed database schema and greatly streamlined its usage. Now we properly use prefix trees with zero byte separated levels. A simple Flag -u converts the database from the previous version.

Support spaces in Discord IDs

And also some refactoring in database functions

Query skill by Discord tag

Use -skill !name to query the registered player's skill using their Discord ID (in form of name#1234). You can type just the first letters of the name and the first match will be returned.

Support basic Steam IDs, fix commander elo calculation

Now you can specify IDs in -skill and -bind as STEAM_1:1:NNNNNNNN too. Average commander elo wasn't parsed correctly. Some rewording in help messages to make the command format more clear.

Version and user binding

Added -version and -bind commands, see -help for details.

Skill queries

Added Hive3 skill queries using the new -skill command. It accepts steam profile URLs, profile IDs or custom (vanity) URLs. See -help for details.