remove old animation examples.

Closes #2027
modified triplot returned value
Scipy2013 Sprint: Cleaning F/C example

I cleaned the F/C example as suggested in the Scipy 2013 sprint. I had
the help of @leouieda on this.

For more information, please see #2181.
Clean-up line and marker demos
colors unsorted
ENH: Added remove methods for legends in figure and axes objects
TST: Added tests for remove of legends on figure and axes objects
Merge pull request #2779 from tacaswell/remove_old_ani

Remove old animation examples.
Merge pull request #2788 from tonysyu/mep12-lines-and-markers-demo

MEP12: Clean-up line and marker demos
Merge pull request #2781 from GBillotey/return_triplot

Triplot returns the artist it adds.
BLD: Replaced assert_is import from nose.tools in test_legend as python 2.6 does not support it
STY: pep8 fixes to test_legend.py
sorted by hue, sat, val
adding axes one at a time
Merge pull request #2798 from cimarronm/legend_remove

Added remove methods for legends in figure and axes objects
Merge pull request #2784 from gabraganca/fc_example

Scipy2013 Sprint: Cleaning F/C example
three column arrangement
docstring and pep8
six and future imports
Merge pull request #2801 from fariza/named_colors

Named colors example