Merge tag 'upstream/2.2.2+svn930'

Upstream version 2.2.2+svn930

diff --cc CMakeLists.txt
index 25448943d46e6c558eb734224325b50aac84fcbf,f279dce3fc742612762db5d22ba557a9137089aa..4aa93ee6ab43e55eb4e3c7c40f01ba6d1490ea47
--- 1/CMakeLists.txt
--- 2/CMakeLists.txt
+++ b/CMakeLists.txt
@@@ -9,12 -9,9 +9,12 @@@ endif(NOT CMAKE_BUILD_TYPE
  
  set(CMAKE_VERBOSE_MAKEFILE ON)
  set(MathGL_VERSION_MAJOR 2)
- set(MathGL_VERSION_MINOR 2.1)
+ set(MathGL_VERSION_MINOR 2.2)
  set(MathGL_SOVERSION 7.2.0)
  
 +set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} -Wl,-z,relro")
 +set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -Wl,-z,relro")
 +set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,-z,relro")
  
  MACRO(MGL_DEPENDENT_OPTION option doc default depends1 force1 depends2 force2)
    IF(${option}_ISSET MATCHES "^${option}_ISSET$")