add test for 509
test fix
fix test for ticket 613
bugfix for ticket 574
proposal for trac issue 595
fixed ring change
Merge pull request #632 from surface-smoothers/proposal.for.ticket.574

bugfix for ticket 574
add types to test bug_574
Merge pull request #633 from surface-smoothers/fix.613

fix test for 613
Merge pull request #631 from surface-smoothers/test.for.ticket.509

add test for 509
Merge pull request #645 from surface-smoothers/fix.proposal.tr595

Fix.proposal.tr595
fix: changes in primdecint.lib
doc: system("random")