Setup .gitignore for Eclipse. Start creating doc strings

.gitignore

@@ -37,10 +37,12 @@ nosetests.xml
 .idea/workspace.xml
 .idea/misc.xml
 .idea
+.settings
 
 # Komodo Files
 *.komodoproject
 
 # OS Files
 .DS_Store
-Thumbs.db
+Thumbs.db
+

gerber/excellon.py

@@ -80,6 +80,16 @@ def loads(data, settings = None, tools = None):
 
 
 class DrillHit(object):
+    """Drill feature that is a single drill hole.
+    
+    Attributes
+    ----------
+    tool : ExcellonTool
+        Tool to drill the hole. Defines the size of the hole that is generated.
+    position : tuple(float, float)
+        Center position of the drill.
+    
+    """
     def __init__(self, tool, position):
         self.tool = tool
         self.position = position