Initialize Configuration::InitRunDir for Windows and writing the PID …

…file

Even if this some Unix specific stuff, we rely on writing this file
in our generic application code. Therefore its path needs to be specified.

This got broken with 9fbc406 which renamed RunDir to InitRunDir, but
didn't re-add it to the Windows #ifdefs.

icinga-app/icinga.cpp

@@ -213,6 +213,8 @@ static int Main()
 		/* Internal constants. */
 		Configuration::PkgDataDir = binaryPrefix + "\\share\\icinga2";
 		Configuration::IncludeConfDir = binaryPrefix + "\\share\\icinga2\\include";
+
+		Configuration::InitRunDir = dataPrefix + "\\var\\run";
 	} else {
 		Log(LogWarning, "icinga-app", "Registry key could not be read. Falling back to built-in paths.");