Includes for linux build.

Some windows compat ensured

src/PityUnit.hh

@@ -8,11 +8,11 @@
 #include "../../../src/std_utils.hh"
 #include "fs_mutex.hh"
 #include "PityTransport.hh"
-//#include "PityPerspective.hh"
 #include <string>
 #include <map>
 #include <memory>
 #include <unordered_map>
+#include <functional>
 
 // Yes, the mem mgmt is purely static on purpose (so far)
 

src/PityUnit.hxx

@@ -15,6 +15,7 @@
 #include <exception>
 #include <memory>
 #include <unordered_map>
+#include <sys/wait.h>
 
 
 namespace pEp {