improved readme

Author: jambun

README.md

@@ -1,2 +1,58 @@
 # user_defined_in_basic
 An ArchivesSpace plugin that displays selected user defined fields in the basic information section
+
+
+## How to install it
+
+To install, just activate the plugin in your config/config.rb file by
+including an entry such as:
+
+     # If you have other plugins loaded, just add 'user_defined_in_basic' to
+     # the list
+     AppConfig[:plugins] = ['local', 'other_plugins', 'user_defined_in_basic']
+
+And then clone the `user_defined_in_basic` repository into your
+ArchivesSpace plugins directory.  For example:
+
+     cd /path/to/your/archivesspace/plugins
+     git clone https://github.com/hudmol/user_defined_in_basic.git
+
+Or if you are after a particular release, download and unzip it from here:
+
+https://github.com/hudmol/user_defined_in_basic/releases
+
+
+## How to configure it
+
+Add an entry to your `config.rb` like this:
+
+     AppConfig[:user_defined_in_basic] = {
+       'accession' => ['boolean_1', 'enum_2', 'real_2'],
+       'digital_object' => [],
+       'resource' => ['string_2', 'date_1', 'boolean_1']
+     }
+
+If you don't have a `:user_defined_in_basic` entry the plugin won't do anything.
+It will log a warning at startup.
+
+The three keys shown (`accession`, `resource`, and `digital_object`) are the
+record types that can have a `user_defined` subrecord. For each key specified
+a `user_defined` subrecord will be automatically added when a new record
+is created through the staff UI, or will be added to an existing record when
+it is edited if it doesn't already have one. Also, the remove button is disabled.
+
+So, in the example shown, no fields are moved to the `Basic Information` section
+for `digital_object` (because the field list is empty), but the presence of the
+`digital_object` key guarantees the addition of a `user_defined` subrecord. To
+disable this behavior, simply remove the key.
+
+For each record type, specify the `user_defined` fields that you would like to
+see in the `Basic Information`.
+
+The fields specified will be moved to the `Basic Information` section and will
+appear in the order specified.
+
+If you specify a key other than the three record types supported, or a field
+that doesn't exist in the `user_defined` record, a warning will be logged at
+startup.
+