add smoothing to hist2d
doc: mv examples to sphinx
doc: add preamble option to winston directive
doc: make oplot example reproducible
doc: start fleshing out objects section
doc typo
update plot_interfaces _plot -> plot
adjust scatterplot
better limits for partial ranges

For example, `plot(1:100, xrange=(20,40))` will now have a yrange of
(20,40) instead of (0,100).
display as png in ijulia
Merge pull request #106 from natj/hist2d_smooth

add smoothing to plothist2d
Merge pull request #108 from jverzani/jv/plot

Jv/plot
allow color=(r,g,b)
Merge branch 'master' of git://github.com/nolta/Winston.jl