fix: remove flake8-putty, fix build_docs

Author: oesteban

.travis.yml

@@ -10,7 +10,7 @@ python:
 
 before_install:
   - python -m pip install --upgrade pip
-  - pip install "flake8<3.0" flake8-putty
+  - pip install flake8
 
 script:
   - flake8 fmriprep wrapper

fmriprep/config.py

@@ -545,9 +545,12 @@ def init_spaces(checkpoint=True):
     if checkpoint:
         spaces.checkpoint()
 
-    internal = workflow.internal_spaces
-    if internal is not None and internal.strip():
-        for ref in internal.split(' '):
-            spaces.add(ref)
-
+    if workflow.internal_spaces:
+        internal = [
+            Reference.from_string(ref)
+            for ref in workflow.internal_spaces.strip().split(' ')
+        ]
+        spaces += [
+            ref[0] for ref in internal if ref[0].fullname not in spaces
+        ]
     workflow.spaces = spaces

setup.cfg

@@ -103,7 +103,3 @@ parentdir_prefix =
 max-line-length = 99
 doctests = True
 exclude=*build/
-putty-ignore =
-    */__init__.py : +F401
-    docs/conf.py : +E265
-    /^\s*\.\. _.*?: http/ : +E501