Update Black to newest version

Updates the Black code-formatter to its newest version and applies it.
They made some small changes to how it handles numeric literals that
affected a few files - both always forcing a "0." prefix on float values
instead of allowing an implicit "0" to be there, as well as only adding
underscore separators if the number has at least 6 digits.

tildes/requirements.txt

@@ -8,12 +8,12 @@ atomicwrites==1.2.1
 attrs==18.2.0
 backcall==0.1.0
 beautifulsoup4==4.6.3
-black==18.6b4
+black==18.9b0
 bleach==2.1.4
 certifi==2018.8.24
 cffi==1.11.5
 chardet==3.0.4
-click==6.7
+Click==7.0
 cornice==3.4.0
 decorator==4.3.0
 dodgy==0.1.9
@@ -90,7 +90,7 @@ stripe==2.8.1
 testing.common.database==2.0.3
 testing.redis==1.1.1
 titlecase==0.12.0
-toml==0.9.6
+toml==0.10.0
 traitlets==4.3.2
 transaction==2.2.1
 translationstring==1.3

tildes/tests/test_simplestring_field.py

@@ -40,7 +40,7 @@ def test_changing_max_length():
 def test_long_string():
     """Ensure a long string fails validation."""
     with raises(ValidationError):
-        process_string("A" * 10_000)
+        process_string("A" * 10000)
 
 
 def test_empty_string():

tildes/tildes/metrics.py

@@ -32,13 +32,13 @@ _HISTOGRAMS = {
     "markdown_processing": Histogram(
         "tildes_markdown_processing_seconds",
         "Markdown processing",
-        buckets=[.001, .0025, .005, .01, 0.025, .05, .1, .5, 1.0],
+        buckets=[0.001, 0.0025, 0.005, 0.01, 0.025, 0.05, 0.1, 0.5, 1.0],
     ),
     "comment_tree_sorting": Histogram(
         "tildes_comment_tree_sorting_seconds",
         "Comment tree sorting time",
         labelnames=["num_comments_range", "order"],
-        buckets=[.00001, .0001, .001, .01, .05, .1, .5, 1.0],
+        buckets=[0.00001, 0.0001, 0.001, 0.01, 0.05, 0.1, 0.5, 1.0],
     ),
 }
 

tildes/tildes/schemas/fields.py

@@ -81,7 +81,7 @@ class ShortTimePeriod(Field):
 class Markdown(Field):
     """Field for markdown strings (comments, text topic, messages, etc.)."""
 
-    DEFAULT_MAX_LENGTH = 50_000
+    DEFAULT_MAX_LENGTH = 50000
 
     def __init__(self, max_length: Optional[int] = None, **kwargs: Any) -> None:
         """Initialize the field with a length validator."""

tildes/tildes/views/login.py

@@ -39,7 +39,7 @@ def finish_login(request: Request, user: User) -> None:
     if request.params.get("keep"):
         request.session.adjust_timeout_for_session(31_536_000)
     else:
-        request.session.adjust_timeout_for_session(86_400)
+        request.session.adjust_timeout_for_session(86400)
 
     # set request.user before logging so the user is associated with the event
     request.user = user