0.5 branch initiated which included the GLPK sources

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/rglp@100 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
GLPK sources not included anymore; archived to 0.5 branch which still has this capability; pushed CRAN version to 0.6-0

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/rglp@101 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
CRAN release

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/rglp@102 edb9625f-4e0d-4859-8d74-9fd3b1da38cb