Merge pull request #1 from paulnicholas/master

materials example
added examples
Merge pull request #11 from paulnicholas/master

update
Merge pull request #12 from paulnicholas/master

updated stress output
Merge pull request #13 from paulnicholas/master

pn_update
test
first distrib commit
deleted all files from devel
deleted devel named example
distrib branch clean up
added first version of material properties

actually only E-modulus and set all sections to 2mm diameter rod by
default
small change to gh def
added some dowload/installation in the readme
got rid of devel readme content
material properties checked with CG + changed naming convention
switched to cable elements for membrane
last commit before sunshine
added I calculation
pn_upate_ignore
added prototype functions for curve constraint