Removed unnecessary regexp part. Added comments about whether using a capturing group is necessary.
Added comment about possibly clearer regexp.
allow markdown in heading cells

italics, bold, math, etc.

closes #3053
up default max_msg_size to 1MB
warn about messages dropped due to oversize
style.min.css shoudl always exist...

as IPython and nbconvert shoudl always be in sync now.
add PYTHONSTARTUP to startup files

closes #2706
Skip import irunner test on Windows.

Closes gh-3544
Merge pull request #3574 from Carreau/correct-mode

correct static path for CM modes autoload

This should also allow to require CM-python mode for ipython mode and
only pass a config options instead of copy-past of all file.
tweak `run -d` message to 'continue execution'

clarify any ambiguity with 'start'.

closes #3464
Merge pull request #3572 from takluyver/win-skip-irunner

Skip import irunner test on Windows.

Closes #3544
Added support for markdown in heading cells when they are nbconverted.
Simplify codemirror ipython-mode

make it a subset of python mode, only with configuration
Use adjustbox to specify figure size in latex
Avoid calling of wrap function in headers of the markdown tpl when is nbconverted.
Added missing space.
We used a better wordwrap function provided by Jinja which let us wrap the titles in the correct way.
Added (to full_html and reveal templates) the possbility to read a custom.css file for tweaking the final html.
Merge pull request #3578 from jakobgager/latex_image_handle

Use adjustbox to specify figure size in nbconvert -> latex

Instead of hardcoding the image size used when compiling latex, a maximum size is specified only.
This way smaller images don't get enlarged. The Sphinx converter use the same approach.
Merge pull request #3495 from lebigot/master

Simplified regexp, and suggestions for clearer regexps.