IfcParse dynamic linking, IFCPARSE_NO_REGEX, fixes for three memory leaks (#76)

* CMake: moved setting link directories before all the projects.

* Added IfcParse_Export header for declaring export macro.

* Added IFCPARSE_STATIC_DEFINE macro to all projects.

* Added include for export macro to swig file.

* Added IfcParse_EXPORT macro for all classes in headers generated by express parser.

* Allow removing boost.regex dependency by defining macro IFCPARSE_NO_REGEX.

* Fixed bug in deletion of ICU converter.

* Added export macro to most of the classes across headers

* Fixed memory leak: delete nested IfcAbstractEntity in EntityArgument.

* Fixed memory leak in destructor of IfcWritableEntity (args values).

src/ifcparse/IfcSpfStream.h

@@ -30,6 +30,8 @@
 #include <fstream>
 #include <string>
 
+#include "../ifcparse/IfcParse_Export.h"
+
 // As of IfcOpenShell version 0.3.0 the paging functionality, which
 // loads a file on disk into multiple chunks, has been disabled.
 // It proved to be an inefficient way of working with large files,
@@ -46,7 +48,7 @@ namespace IfcParse {
 	/// which only one is simultaneously kept in memory, for files
 	/// that define their entities not in a sequential nature, this is
 	/// detrimental for the performance of the parser.
-	class IfcSpfStream {
+	class IfcParse_EXPORT IfcSpfStream {
 	private:
 		FILE* stream;
 		char* buffer;