Fix a "pure virtual method called" exception on server termination

Author: gaudryc

main/WebServer.cpp

@@ -609,7 +609,6 @@ namespace http {
 			{
 				if (m_pWebEm == NULL)
 					return;
-				m_pWebEm->SetSessionStore(NULL);
 				m_pWebEm->Stop();
 			}
 			catch (...)

webserver/cWebem.cpp

@@ -59,6 +59,8 @@ cWebem::cWebem(
 }
 
 cWebem::~cWebem() {
+	// Remove reference to CWebServer before its deletion (fix a "pure virtual method called" exception on server termination)
+	mySessionStore = NULL;
 	// Delete server (no need with smart pointer)
 }