only check for formatters on instances

use inspect.isclass to disallow unbound methods,
not type checking on the method itself
Print exception instead of "KeyboardInterrupt"

Whenever a KeyboardInterrupt exception occurs in the shell, we should
print the actual exception instead of the string "KeyboardInterrupt".
This is needed to support exceptions inherited from KeyboardInterrupt.
Fix test_get_exception_only() for Python 3
remove _valid_formatter

check in _safe_get_formatter_method

- reject classes
- allow any callable...
- ...except on objects that lazily produce callables at any attribute
gh-7053: check for OSError during rehashx()
Make the model.views dict a dict of promises for views

Otherwise, there is a race condition where the model doesn't know about views until they are actually created.
Kill the layout manager
Fix scrolling for large outputs
Fix scroll/resize handle missing behavior.
Fix, prevent notebook from having its height set on pager display
Increase pager handle size.
remove special handling of ipython_kernel in launcher

- set JPY_PARENT_PID and JPY_INTERRUPT_EVENT env variables for all kernels
- no custom kernel args other that console passthrough
- use devnull instead of `--no-stdout` (comments claim it shouldn't work, but tests suggest it does - let's keep an eye on this)
moving, checking MathJax typesetting to WidgetView

widget rendering should not fail hard if MathJax is not available
also setting text in widget.typset
reversing order of arguments, as text may already exist
moving typeset to DOMWidgetView
accept node or selection
Merge pull request #7069 from jdemeyer/print_keyboardinterrupt

Print exception instead of "KeyboardInterrupt"
Merge pull request #7077 from jdemeyer/path_oserror

check for OSError during rehashx()

closes #7053
add py3compat.buffer_to_bytes_py2

casts buffer-providing objects to bytes

needed for pickle.loads on buffers