New patch to singular (trac 13770) for sage 5.12, 5.13 and 6.0

Package-Manager: portage-2.2.7
new singular patch (trac 13770) for sage 5.12, 5.13 and 6.0

Package-Manager: portage-2.2.7
bumping libsingular dependency in 5.12 and 6.0. Simultaneous upgrade to latest singular 3.1.5 recommended. 6.1 is supposed to use singular 3.1.6

Package-Manager: portage-2.2.7