Shrimp Shader Generator FLTK2 GUI (SVN)

Updated some information on the usage for the shadowing and masking functions.

- Change the square size around pad shader parameter
- Test of a documentation system for Shrimp blocks base on xml file information.(will start firefox from the menu help if you don't have it check the doc folder and look for index.html from your browser) the doc it's generate everytime you restart Shrimp to take account your last custom blocks(will put an option later in the preference)
- Correct some syntax on some block that create xslt issues during parsing

Fixed some commit issues, IFD/bgeo/OTLs work thanks to Hans Hoogenboom.

- block property that are also shader parameters will have a orange square.

NEW: created some functions to handle arrays

FIX: array are declared properly as local variables

ENH: code cleanup

NEW: contributor

Improved use of PI defines.

Patch by Matthew Lawrence to replace the awful round corners block code by vertex arrays and GL_POLYGON_STRIP. Cleaning up the code, making it MESA stack compatible, and generally improving the performance dramatically.