new measurement methods
return axes and axes bounds from plotting.utils.draw
Merge pull request #561 from ndawe/master

[MRG] new measurement methods
workspace.fit add return_nll argument
Merge pull request #562 from ndawe/master

[MRG] workspace.fit add return_nll
draw() if graph is the first object, don't use the A option since that draws lines on the plot for the axes
minor fix
Merge pull request #563 from ndawe/master

draw() if graph is the first object, don't use the A option
set yaxis and xaxis limits manually in the plot function
add graph.num_points setter and getter
new axes() on pads create and return axes
ratioplot template
add fill_value argument to Hist.divide
RatioPlot: set tick lengths
RatioPlot: draw horizontal lines in ratio pad
_limits_helper: don't raise ValueError and instead return reasonable values if min=max