some spelling, grammer, and rst format fixes
some spelling, grammer, and rst format fixes

SylvainCorlay/ipywidgets,jupyter-widgets/ipywidgets,ipython/ipywidgets,ipython/ipywidgets,cornhundred/ipywidgets,cornhundred/ipywidgets,cornhundred/ipywidgets,jupyter-widgets/ipywidgets,jupyter-widgets/ipywidgets,jupyter-widgets/ipywidgets,SylvainCorlay/ipywidgets,cornhundred/ipywidgets,cornhundred/ipywidgets,ipython/ipywidgets,SylvainCorlay/ipywidgets,ipython/ipywidgets,SylvainCorlay/ipywidgets,ipython/ipywidgets