Allow filename with extension in find_cmd in Windows.

closes gh-3316 (hopefully)
Add a mode to exec code in %debug magic
Document the new usage of %debug
When a notebook is written to file, name the metadata name u''.
Drop patch for compatibility with pyreadline 1.5

Closes gh-1307
Removed unnecessary regexp part. Added comments about whether using a capturing group is necessary.
Added comment about possibly clearer regexp.
Set calling program to the empty string, when argv not in sys

It might happen, then the sys module has no argv, when embeding IPython
into other programs with IPython.embed(). In that case, just set the
calling program to "" or other logic in IPython will crash - for
instance when checking for command line arguments.
%store -r restores saved aliases and directory history, as well as variables.
fix HTML capitalization in exporter classes
notebook supports raw_input and %debug now

updates Frontend-Kernel model example notebook to reflect this.

closes #3489
If template is not found by name, exception thrown.
fix nbconvert filter validation
Get Tracer working after ipapi.get replaced with get_ipython

Commit 790f731 replaced `ipapi.get` with a `get_ipython` function,
that changed the API slightly, returning None when no InteractiveShell
instance has been registered.
Merge pull request #3511 from punchagan/fix-tracer

Get Tracer working when no IPython instance is running
use register_filter() for registering user filters
use bootstrap `disabled` instead of `ui-state-disabled`

in menubar
update CodeMirror component to 3.14

I believe this closes #3361, if @fperez and/or @fonnesbeck can confirm.
make css highlight style configurable
Merge pull request #3512 from jakevdp/nbconvert_filter

fix nbconvert filter validation