python: fix flake8 warnings and format with black

Most of the flake8 warnings in this repository were fairly trivial,
so fixed them.  The "openbmctool" is 7000+ lines of pretty heavily
warned code, so just disabling that one.  Format everything with
black.

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: Icb3f6ee9bf03dece58785f7af00617c87a84aa65
diff --git a/.linter-ignore b/.linter-ignore
new file mode 100644
index 0000000..1fd098c
--- /dev/null
+++ b/.linter-ignore
@@ -0,0 +1 @@
+openbmctool/openbmctool.py