Pipe/round-bar clamp with hinge and captive nut

This OpenSCAD script will generate a 2 part hinged clamp which can be used to attach things to pipes or round bars such as handlebars, pencils, canes etc.
The script is fully parametric and only requires you to input the diameter of your pipe, how thick you want the clamp to be and what sized nuts/bolts filament (for use as a hinge pin) you want to use

Radial tolerances and other values can be altered from stock if you want
The top, bottom or both can be optionally generated by changing a boolean control variable
Mouse ears can be added easily by changing a boolean control variable

@author Mark Gaffney
@version 0.5a
@date 2012_07_25

@todo
fix mouse ear positions for more rounded version

@warning
@note
Changes from previous versions:

v0.5a

• fix to ensure that bolt hole passes all the way through arm on top part
  

v0.5

• make bolt hole pill shaped to allow for wiggle
  

v0.4

• Refined shape
  

• Made holes optional
  

v0.3a

v0.2

• add option to add mouse-ears
  

v0.1

• first attempt