Add instructions on how to configure the bot and run it in README

Signed-off-by: Alek Ratzloff <alekratz@gmail.com>

README.md

@@ -1,3 +1,109 @@
 # Omnibot
 
 IRC bot with plugin/module support.
+
+# Preparation
+
+Omnibot is written in Elixir, which I am still learning. There are no releases yet, so there is no
+"installation" process.
+
+There are two ways to run omnibot: as a standalone process, or as a docker container.
+
+## Standalone
+
+### Requirements
+
+* Elixir 1.10+
+* A Rust compiler
+    * You can install Rust via https://rustup.rs
+    * I'm annoyed by this too. I'm working on getting rid of this dependency.
+
+### Building
+
+Run these lines to build:
+
+```
+mix local.hex
+mix local.rebar3
+mix deps.get
+```
+
+Confirm this by running `mix test`
+
+## Docker
+
+All you need for this is to be able to run `docker` and `docker-compose` - nothing else.
+
+# Configuration
+
+Runtime configuration is specified via an Elixir script, in **omnibot.exs** by default.  [An example
+configuration](https://github.com/alekratz/omnibot/blob/master/omnibot.example.exs) is also provided
+in the project root. Changing the configuration file can be done setting the environment variable
+`OMNIBOT_CONFIG` to the path of the configuration file to use.
+
+## Configuration keys
+
+* `server` - the IRC server to connect to. **(required)**
+* `nick` - the IRC nickname to use for the bot. **(optional, default "omnibot")**
+* `user` - the IRC username to use for the bot. **(optional, default "omnibot")**
+* `real` - the IRC realname to use for the bot. **(optional, default "omnibot")**
+* `port` - the port to connect to the server on. **(optional, default 6667)**
+* `ssl` - whether to use SSL or not. Note that IRC usually uses port 6697 for SSL. **(optional, default false)**
+* `channels` - 
+* `plugins` - a list of plugins to load and their configuration. **(optional, default [])**
+* `plugin_paths` - a list of locations to look for additional plugins. **(optional, default [])**
+
+### Plugin configuration
+
+Plugin configuration is done as a list of either:
+
+* a plugin name, e.g. `Core` or
+* a *tuple* of plugin, and plugin configuration, e.g.
+  `{Omnibot.Contrib.Fortune, channels: ["#general"]}`
+
+#### Plugin channels
+
+All plugins have a `channels` configuration value, which determines which IRC channels the plugin
+will be active in. Alternatively, if you want a plugin to be active in all channels, you can specify
+`channels: :all` in the plugin configuration instead of a list. This will also include channels
+specified *only* in their channel config, which do not appear in the root-level "channels" config.
+In other words, if "#foo" channel is joined only because it is specified by `SomePlugin`, all other
+plugins that join `:all` will also be active in this channel. (author's note: this is probably not
+desired behavior, but that's the behavior as of now)
+
+## Gotchas
+
+* In the configuration file, a `config` variable **must** be assigned to an `%Omnibot.Config {}`
+  structure.
+* The list of loaded plugins **must** include the `Core` plugin for correct functionality. This
+  plugin handles things like joining channels and reconnecting to the server if the connection is
+  lost.
+
+# Usage
+
+This section assumes that you have created a configuration file and are ready to run the bot.
+
+## From standalone
+
+Ensure you have your configuration saved in omnibot.exs (or wherever you decide to point it), and
+then run:
+
+`mix run --no-halt`
+
+This will start the application up and running.
+
+## Using Docker
+
+Dockerfile, docker-compose.yml, and docker.env files have been provided so you can write your
+omnibot.exs configuration and start a docker container. You should simply be able to run
+`docker-compose up -d` and be good to go.
+
+# Final notes
+
+Since this is a BEAM application, you will sometimes see error messages pop up. This is normal
+behavior. If you see endless error messages (e.g. can't connect), then something is probably wrong
+and checking the logs may help you determine the issue.
+
+# Plugins
+
+TODO: short intro about plugins and links to examples