multi-word arguments should use dashes (#37)

README.rst

@@ -27,7 +27,7 @@ The library has been tested for now with following devices:
 
 .. NOTE::
   If no one has contributed a devinfo from your device (see devinfos/ directory),
-  please feel free to contribute one by typing `songpal dump_devinfo <filename>` 
+  please feel free to contribute one by typing `songpal dump-devinfo <filename>` 
   and creating a pull request on this repository. 
   This information can later be useful for extending the support for those devices.
 
@@ -224,7 +224,7 @@ Executing custom commands
 -------------------------
 
 For experimenting it can be useful to execute arbitrary commands against the endpoint.
-You can access the available methods by calling ``songpal list_all``.
+You can access the available methods by calling ``songpal list-all``.
 
 ``command`` can be used for that as follows:
 
@@ -254,7 +254,7 @@ Reporting bugs or supported devices
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 When reporting bugs or informing about supported device not listed above,
-please consider attaching the output of ``songpal dump_devinfo`` with your report.
+please consider attaching the output of ``songpal dump-devinfo`` with your report.
 
 
 API information