Export symbols in order to support shared libraries (#54)

* Add BAC_ROUTING compile definition

* Reorder cmake

* Fix OpenSSL support: support both 1.0 and 1.1t pus

* Explicitly export symbols, hidden by default

* Build shared libraries on travis using cmake

* Learn Makefile about static library

* Fix build using mingw with cmake

* Do not cleanup twice or after potential free

src/bacnet/proplist.h

@@ -26,6 +26,7 @@
 
 #include <stdint.h>
 #include <stdbool.h>
+#include "bacnet/bacnet_stack_exports.h"
 #include "bacnet/bacdef.h"
 #include "bacnet/bacenum.h"
 #include "bacnet/rp.h"
@@ -46,11 +47,14 @@ struct special_property_list_t {
 extern "C" {
 #endif /* __cplusplus */
 
+    BACNET_STACK_EXPORT
     unsigned property_list_count(
         const int *pList);
+    BACNET_STACK_EXPORT
     bool property_list_member(
         const int *pList,
         int object_property);
+    BACNET_STACK_EXPORT
     int property_list_encode(
         BACNET_READ_PROPERTY_DATA * rpdata,
         const int *pListRequired,