expand on readme

Author: Adrian Tschira

README.md

@@ -8,22 +8,38 @@ Labelprinterkit's simple layout engine can be used to declaratively create
 simple labels:
 
 ```python
->>> class MyLabel(Label):
-...     items = [
-...         Text(), Text()
-...     ]
-...
->>> l = MyLabel("text1", "text2")
->>> printer.print_label(l)
+from Labelprinterkit import backends, items, label
+from Labelprinterkit.printers.brother_pt700 import P700
+
+# Define the layout of our label
+# We define a single row with two text items.
+# In real usage, you will probably want to change the font of the text.
+class MyLabel(label.Label):
+    items = [
+        items.Text(pad_right=50), items.Text()
+    ]
+
+# Instantiate the label with specific data
+l = MyLabel("text1", "text2")
+# scan for a USB printer using the PyUSBBackend
+printer = P700(PyUSBBackend.auto()
+# Print!
+printer.print_label(l)
 ```
 
 The Following printers are currently supported:
 
  * Brother P-Touch PT-700 (aka P700)
 
-The following printers will probably work, but are not tested:
+The following printers will probably work, as they are supposedly identical,
+but have not been tested (please tell us if they do!):
 
  * Brother H500
  * Brother E500
 
+The following backends are currently supported:
+
+ * USB Printer Device Class via PyUSB
+
 The official source of this repository is at https://git.scc.kit.edu/scc-net/labelprinterkit.
+Pull requests and issues are also accepted on github at https://github.com/notafile/labelprinterkit.