repo needs updating

[drjfloyd]

With the recent issues with radcal revisted the cor repo and the matlab plotting was broken. Looks like it is because in part we don't make a git.txt file. Have added build scripts and changed correlations.f90 to write git.txt files. Will work on getting the plots working and on making sure guides build.

[drjfloyd]

plotting script and guide building works again.

Will need to check manual for formatting.

@rmcdermo @mcgratta
On page 1 the cor manual gives the fire.nist.gov/fds as a location to get the cor files. This page is dead and the pages.nist.gov/fds page doesn't have any links for cor. Should this be changed to the git repo or is there a cor page somewhere on pages.nist.gov.

[drjfloyd]

updated document for emissive power change for the solid flame model.
tweaked the cover page format for the git repo to be more like the FDS guides.

still need to fix the page 1 website.
-could just give the git repo for cor
-could give the pages site for fds and note there is a link to the firemodels repo where cor lives