travis: fix build problems

* remove "in-tree vs generated" check as there is no in-tree anymore
* add protobuf to requirements-dev
* use requirements-dev in tox

travis: do not diff generated against (missing) in-tree messages

travis: in tox env, use requirements-dev

.travis.yml

@@ -41,8 +41,6 @@ before_script:
     - ./trigger-travis.sh
 
 script:
-    # check that generated protobuf messages are identical to in-tree ones
-    - ./tools/build_protobuf messages.tmp && diff -ur messages.tmp trezorlib/messages && rm -r messages.tmp
     - python setup.py install
     - flake8
     - tox

requirements-dev.txt

@@ -3,3 +3,4 @@
 pytest>=3.5.0
 mock>=2.0.0
 flake8
+protobuf

tox.ini

@@ -7,9 +7,7 @@ envlist =
 
 [testenv]
 deps =
-    -rrequirements.txt
-    pytest
-    mock
+    -rrequirements-dev.txt
 commands =
     python -m compileall trezorlib/
     python trezorctl --help