fix a bug for data dirs read from /etc/spring/datadir & docu fix

was using " " instead of ":" as separator
thanks to jepperc for finding this!

rts/System/FileSystem/DataDirLocater.cpp

@@ -233,12 +233,13 @@ void DataDirLocater::LocateDataDirs()
 			while (fgets(lineBuf, sizeof(lineBuf), fileH)) {
 				char* newLineCharPos = strchr(lineBuf, '\n');
 				if (newLineCharPos) {
-					// end the string at the  it an empty string
+					// remove the new line char
 					*newLineCharPos = '\0';
 				}
 				// ignore lines consisting of only whitespaces
 				if ((strlen(lineBuf) > 0) && strspn(lineBuf, whiteSpaces) != strlen(lineBuf)) {
-					dd_etc = dd_etc + " " + SubstEnvVars(lineBuf);
+					// append, separated by cPD (depending on OS): ';' or ':'
+					dd_etc = dd_etc + (dd_etc.empty() ? "" : cPD) + SubstEnvVars(lineBuf);
 				}
 			}
 			fclose(fileH);