flesh out the readme

Cargo.lock

@@ -23,7 +23,7 @@ checksum = "f8aac770f1885fd7e387acedd76065302551364496e46b3dd00860b2f8359b9d"
 
 [[package]]
 name = "axfive-matrix-dicebot"
-version = "0.1.1"
+version = "0.1.2"
 dependencies = [
  "nom",
  "rand",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "axfive-matrix-dicebot"
-version = "0.1.1"
+version = "0.1.2"
 authors = ["Taylor C. Richberger <taywee@gmx.com>"]
 edition = "2018"
 license = 'MIT'

README.md

@@ -1,3 +1,66 @@
 # axfive-matrix-dicebot
 
-Just a simple dicebot for matrix written in Rust.  Currently there's not much to it.
+Just a simple dicebot for matrix written in Rust.  It might have some sort of
+stability issues.  I haven't seen it die in the wild, but it's mostly
+hacked-together code that has been pretty lightly tested and reviewed, and I'm
+certain that some things are still left undone, like interacting properly with
+rate-limiting, and dealing with any sort of sporadic error (like being suddenly
+deauthenticated and having to reauthenticate).
+
+This was mostly built as a fun way of
+
+* Experimenting with writing an async program in Rust that does something real
+* Experimenting with writing a bot for Matrix
+* Experimenting with writing a simple parser using [nom](https://github.com/Geal/nom)
+
+All of which was new territory for me.
+
+## Usage
+
+To use it, you can invite the bot (@axfive-dicebot:matrix.org) to any room you
+want, and it will automatically jump in.  Then you can simply give a dice
+expression as such:
+
+```
+!roll 4d6
+!r 4d7 + 3
+!r 3d12 - 5d2 + 3 - 7d3 + 20d20
+```
+
+And the dicebot should reply with the result in short order.
+
+You can also run it yourself by creating a bot account, building the dicebot
+program, and creating a config file that looks like this:
+
+```ini
+[matrix]
+home_server = 'matrix.org'
+
+[matrix.login]
+password = 'thisismypassword'
+type = 'm.login.password'
+user = 'axfive-dicebot'
+```
+
+Of course replacing all the necessary fields.  Then you can run the built
+"dicebot" binary pointing at that, and it will log in and hum along and do its
+thing.
+
+You can also just run it on the command line with the `dicebot-cmd` command,
+which expects you to feed it one of the command expressions as shown above, and
+will give you the plaintext response.
+
+## Future plans
+
+None, really.  This is not a very serious project and I'm not planning on doing
+much heavy maintenance or anything of the sort.  This was mostly for fun.  If I
+get some motivation to work it up, I might at some point do some things like:
+
+* Actually have it handle rate-limiting and other errors properly.
+* Add more syntax to the dice expressions, maybe making it possibly have more
+  features that [Avrae](https://avrae.io/commands#roll) offers.
+* Potentially add more commands.
+
+I would happily accept any sort of pull requests for extra functionality or more
+robustness if anybody wants to actually use it.  The code is built to hopefully
+be relatively easy to extend (with things like new commands).