check for Python 3.2

in setup.py and init

treats unsupported 3.x < 3.3 like unsupported 2.x
reset readline after running PYTHONSTARTUP

should avoid conflicts between IPython and Python completions
more semantic icons
remove auth and tree from ipython.less

@minrk said it's the right thing to do
use fixed-width icons, closes #5555
book icon for notebooks, color folders differently

This allows us to use the generic file icon for text files, etc, down
the line.
update components with marked-0.3.2
update install instructions to use --user for pip
Fixing bug #5607

Changed the method from extends to merge which merges the two arrays as
desired - With Freyert
Fix typo in storemagic module docstring

Closes gh-5611
Merge pull request #5619 from takluyver/i5611

Fix typo in storemagic module docstring
fixed a typo in IPython.core.formatters
Merge pull request #5620 from garrison/patch-1

fixed a typo in IPython.core.formatters
don't ensure_ascii in JSON messages in Session
Fixed Issue #4012 Added Help menubar link to Github Flavored Markdown doc
Better lessc detection/handling.

* lessc@1.5.0 now invalid
* more help if lessc not found
Merge pull request #5633 from ahmadia/improve_no_lessc_error

Provide more help if lessc is not found.
Merge pull request #5613 from nilenoether/fix-5607

Fixing bug #5607 - Some shortcut missing from help reference.
Add preprocessor that clears cell outputs
Fix copyright on clearoutput.py