Add debug message.
End transaction immediately when no switch present.
Add test for dispatch to all switch but no switch exist.
Keep command line entry list order.
Refactor .feature
* rename nw_dsl.conf -> network.conf
* Remove Scenario Outline template from Ruby code.
tream switch_manager special in switch daemon.
Merge pull request #297 from y-higuchi/switchd_branching

Refactor switch event forwarding interface
Do not generate temporary files in src/** while running tests.
On `rake travis`, run some specs that doesn't require sudo.
Run non-sudo echo message tests at `rake travis`.
add the check that action-vendor-length is a multiple of 8
Make action_*_to_string to public.
improve argument checking in SetIpTos.initialize()

Only the 6 high-order bits of the ToS octet are allocated to DSCP value.
When it comes to constructing a C structure for OFPAT_SET_NW_TOS action,
there is a respective assertion in function append_action_set_nw_tos().
Once the assertion is triggered, the controller will terminate with a
message:

...trema/src/lib/openflow_message.c:1547: append_action_set_nw_tos:
Assertion `( nw_tos & ~0xfc ) == 0' failed.

A sample code triggering this would be:

send_flow_mod_add(dpid, :actions => [ SetIpTos.new(1) ])

The check added to SetIpTos.initialize() makes sure an exception is
thrown before the invalid value reaches the C function, such that it is
now possible to handle the error at Ruby level.
add body length check to VendorAction.initialize()

For OFPAT_VENDOR the action body length is defined to be a multiple of
8. Add a check to the constructor to make the Ruby layer detect the
error condition rather than the C layer.
Merge pull request #298 from infrastation/develop

improve input checks in Ruby action classes
update unit tests for the new input checks

Add two test cases that expect an ArgumentError to be raised:

* OFPAT_SET_NW_TOS with ToS value 1 (not a multiple of 4)
* OFPAT_VENDOR with body length 9 (not a multiple of 8)
Fix VendorAction's body length check.
Merge pull request #300 from infrastation/develop

update unit tests for the new input checks
Fix the NameError of Trema::PacketQueue (refs #299)
Fix copy & paste error (refs #299)