Minimal changes to import IPython from IronPython
Merge remote-tracking branch 'upstream/master'
Summary of changes:

1) IPython/core/compilerop.py: IronPython __future__ flags are non-standard,
Solution try/except; comment added

2) IPython/core/completer.py: __main__ was undefined, due to local mistake in
creating IronPython scope; removed this tweak

3) IPython/core/prompts.py: os.getuid() is not defined (IronPython bug; see:
https://mail.python.org/pipermail/ironpython-users/2014-February/016812.html)

4) IPython/lib/inputhook.py: ctypes SystemError; comment added

5) IPython/utils/process.py and IPython/utils/_process_cli.py: adds a
new _process_cli.py which would handle the processes under cli;
fixed os.pathsep

6) IPython/utils/io.py: devnull opened in append mode; changed to "w"

7) New issue: IPython/external/decorator/_decorator.py: IronPython doesn't
have _getframes, unless FullFrames is set to true; comment added
require print_method to be a bound method

closes #4990
add _valid_formatter

for determining whether a method is valid

should properly reject unbound methods of both compiled and Python classes, and allow any other Python callable.
don't allow LazyConfigValue on private names

avoids populating Config objects with `_repr_foo_`, etc.
rewrite _valid_formatter

- explicitly forbid method_descriptor
- explicitly allow builtin_function
- use inspect.getcallargs for any other callable
flush replies when entering an eventloop

avoids possible hangs when the GUI eventloop prevents queued replies from being sent
Merge remote-tracking branch 'upstream/master'
Removed another of the tweaks, and added a note in  that it is largely untested.
don't create js test directories unless they are being used

just moves a setup block from `__init__` to `launch`
Corrected a lot of small misuses of the new flex model.
fab css
Updated alignment widget example.
Automatic width adjustment for flex0
fab css
Change stretch to flex-start
fab css
Revert "fab css"

This reverts commit a45a2c0f2ae26e7b731dc54965a6b224a39454b4.
Revert "Change stretch to flex-start"

This reverts commit 774073116dd4195037c452d48f05b432bba38801.