update Readme with source path

Author: lievenhey

README.md

@@ -189,6 +189,8 @@ Options:
                            libraries.
   --appPath <path>         Path to folder containing the application executable
                            and libraries.
+  --sourcePaths <paths>    Colon separated list of extra paths to the source
+                           code.
   --arch <path>            Architecture to use for unwinding.
   --exportTo <path>        Path to .perfparser output file to which the input
                            data should be exported. A single input file has to
@@ -326,6 +328,9 @@ For easier navigation, you can simply click on a line and the other view will ju
 You can follow function calls with a double click.
 In the sourcecode view you can press ctrl+f or press the search icon to open a search window.
 
+If you have the sources in different directory, you can use `--sourcePaths` or the settings to
+select tell the disassembler to search there for the source code.
+
 ## Known Issues
 
 If anything breaks in the above and the output is less usable than `perf report`, please