Update Valentina.pro to recognize GCC version 8.

--HG--
branch : release

Valentina.pro

@@ -16,6 +16,10 @@ count(LIST, 1, >): error("The build will fail. Path '$${OUT_PWD}' contains space
 unix {
     *g++* {
         GCC_VERSION = $$system("g++ -dumpversion")
+        contains(GCC_VERSION, ^8.*$) {
+            message( "g++ version 8.x found" )
+            CONFIG += g++8
+        } else {
             contains(GCC_VERSION, ^7.*$) {
                 message( "g++ version 7.x found" )
                 CONFIG += g++7
@@ -39,6 +43,7 @@ unix {
             }
         }
     }
+}
 
 TEMPLATE = subdirs
 SUBDIRS = src