Bump master version to 3.1.0

Signed-off-by: allexzander <blackslayer4@gmail.com>

VERSION.cmake

@@ -1,6 +1,6 @@
 set( MIRALL_VERSION_MAJOR 3 )
-set( MIRALL_VERSION_MINOR 0 )
-set( MIRALL_VERSION_PATCH 82 )
+set( MIRALL_VERSION_MINOR 1 )
+set( MIRALL_VERSION_PATCH 0 )
 set( MIRALL_VERSION_YEAR  2020 )
 set( MIRALL_SOVERSION 0 )