upgrade hl version to 1.15 (cmake)

CMakeLists.txt

@@ -1,7 +1,7 @@
 cmake_minimum_required(VERSION 3.1)
 
 set(HL_VERSION_MAJOR 1)
-set(HL_VERSION_MINOR 14)
+set(HL_VERSION_MINOR 15)
 set(HL_VERSION_PATCH 0)
 set(HL_VERSION ${HL_VERSION_MAJOR}.${HL_VERSION_MINOR}.${HL_VERSION_PATCH})