Allow curves to be manipulated in Python

[Nick Draper]

From QTIPLOT handbook:

All the curves in a plot layer can be customized in terms of color, line width and line style. Here's a short script showing the corresponding functions at work:

t = newTable("test", 30, 4)
for i in range(1, t.numRows()+1):
	t.setCell(1, i, i)
	t.setCell(2, i, i)
	t.setCell(3, i, i+2)
	t.setCell(4, i, i+4)

l = plot(t, (2,3,4), Layer.Line).activeLayer() # plot columns 2, 3 and 4
for i in range(0, l.numCurves()):
	l.setCurveLineColor(i, 1 + i) #curve color is defined as an integer value
	l.setCurveLineWidth(i, 0.5 + 2*i)

l.setCurveLineStyle(1, QtCore.Qt.DotLine)
l.setCurveLineStyle(2, QtCore.Qt.DashLine)

[Nick Draper]

Bulk move of tickets at the end of iteration 28

[Nick Draper]

"New" tickets moved at the code freeze of iteration 29

[Nick Draper]

Bulk move of tickets to iteration 31 at the iteration 30 code freeze

[Russell Taylor]

Add ability to modify a curve's characteristics from Python. Re #2655.

A plotted curves colo(u)r, width and line style can now be changed via the Layer object in Python.

Changeset: 2d84d7687a1fd973e9d537dd5380dd30916f4e7f

[Russell Taylor]

The documentation at http://www.mantidproject.org/MantidPlot:_1D_Plots_in_Python has also been updated.

[Peter Parker]

Script ran fine. Tried to break it by generally making a nuisance of myself but couldn't.

[Stuart Campbell]

This ticket has been transferred to github issue ​3502