Update README.md

Up version number and include info regarding customising the config values

README.md

@@ -13,7 +13,7 @@ Add the role to the `galaxy.yml` file of Trellis :
 - name: trellis-redis
   src: https://github.com/E-VANCE/trellis-redis
   type: git
-  version: 0.3.0
+  version: 0.3.1
 ```
 
 Run `ansible-galaxy install -r galaxy.yml` (or `trellis install galaxy` is you have [trellis-cli](https://github.com/roots/trellis-cli)) to install the new role.<br>
@@ -24,4 +24,10 @@ roles:
     - { role: trellis-redis, tags: [redis]}
 ```
 
-After adding the role to the above files and running the install, provision your Vagrant box with `vagrant reload --provision` (if it's running) or `vagrant provision` (if it's not). If you haven't provisioned the box yet simply run `vagrant up` or `trellis up` is you have [trellis-cli](https://github.com/roots/trellis-cli) installed.
+After adding the role to the above files and running the install, provision your Vagrant box with `vagrant reload --provision` (if it's running) or `vagrant provision` (if it's not). If you haven't provisioned the box yet simply run `vagrant up` or `trellis up` if you have [trellis-cli](https://github.com/roots/trellis-cli) installed.
+
+Custom config
+----------------
+You may want to edit the `maxmemory`-values in `/defaults/main.yml` if for example 2 GB isn't enough for your setup or another policy should be used.
+
+A future version of this role will include the possibility for customisations to be made without the fear of overwrites on updating – thus be aware that **any modifications made here are *not* Update-proof**!