Fix cmdline --port argument

Bug fixes

• Ensure --port value is handled as a number not a string by client.l

Add many new commands and bug fixes

New features

• [commands] Add the following Hash COMMANDS: HDEL, HEXISTS, HGET, HGETALL, HKEYS, HLEN, HMGET, HSET, HSTRLEN, HVALS
• [commands] Add the following List COMMANDS: LPUSH, LRANGE, LREM, LSET, LTRIM, RPOP, RPOPLPUSH
• [commands] Add the following String COMMANDS: APPEND, MSET, MGET, STRLEN
• [client] Add --commands to view the list of all commands
• [client] Add --encrypt and --decrypt options to encrypt/decrypt data using a GPG keypair
• [client] Add -- option to read last argument data from STDIN

Bug fixes

• Ensure listening on a socket will abort after *KV_abort seconds
• Reading frorm a socket shouldn't return "no data" or "unknown data" if there's no data. It should just print an empty string.
• Errors should throw/raise an error with the message, for the client to parse
• Perform more validations on individual commands, ex: ensuring a Key is a list, etc
• Temporarily disabled integrations tests because they cause false/positives

Misc changes

• Change the way IDENT and AUTH is performed in client and server
• Client doesn't print "OK " anymore for every command
• Simplify much of the kv command processing code

v0.15.1

• Move the global list of all keys to '%stats%/keys' so it can't be deleted or modified
• Allow 'EXISTS' command on all keys including keys prefixed with '%stats%/'

Library code consolidation

• Consolidate all server library code into one file: libkv.l
• Fix loading of module.l
• Simplify storage location and settings for temporary/lock files
• Explicitly make the child exit when it's finished processing

Minor hotfixes

0.14.2 (2020-07-30)

• Ensure clients actually exit when a 'CLIENT KILL' command is received

0.14.1 (2020-07-30)

• Ensure clients can poll, by listening with (while) instead of (when)
• Update documentation with examples of 'CLIENT' commands

Add persistence and new commands

• Fix bug where client IP is not saved in client list
• Fix bug where client would not disconnect when sent a kill command
• Add persistence which writes commands in an AOF using WAL method
• Saves and restores a DB from disk
• Replays the AOF after restoring the DB
• Add 'SAVE' and 'BGSAVE' commands
• Add 'CLIENT' command
• Add 'PING' command
• Add 'EXISTS' command
• Add 'GETSET' command
• Add 'CONVERT' command
• Remove 'LOLWUT' command
• Run BGSAVE as a scheduled task
• Add statistics for 'persistence'
• Add option to save the DB in binary format
• Add and fix unit tests
• Add timestamp to output and cleanup error messages etc
• Don't require IDENT to be sent by the client during auth
• Fix problem where messages were lost, abort a client connection that takes too long (60s)
• Major optimization, RPUSH with multiple elements is O(N) instead of O(2^N)
• Other minor fixes and code cleanup