disable crosshair in titled plot

[KyleQianliMa]

Description of work

This PR re-introduces crosshair into mantidworkbench plotting module. EWM 10075.
To address part of the issue found during smoking test, the crosshair is automatically disabled in titled plots, enabled in contour plots. There will be a following PR to also disable this in 3D plots to address EWM 10076.

Summary of work

Fixes #xxxx.

Further detail of work

To test:

Testing is easy, check 3 things: 1. crosshair is enabled in general single axis plots. 2. check it's disabled in tiled plots. 3. check it's enabled in contour plots.

To test crosshair is enabled in single-axis plot, either load any data you have or do:

plt.plot([1,2,3], [3,2,1])
plt.show()

check crosshair can be enabled and works properly.

To test crosshair is disabled in titled plots, do:

fig, ax = plt.subplots(2,2)
ax[0,0].plot([1,2,3],[3,2,1])
ax[0,1].plot([1,2,3],[1,2,3])
plt.show()

the crosshair button should be hidden from user now.

.

Finally, to test the crosshair is enabled in contour plots, do:

data = Load('SANSLOQCan2D.nxs')

fig, axes = plt.subplots(subplot_kw={'projection':'mantid'})

# IMPORTANT to set origin to lower
c = axes.imshow(data, origin = 'lower', cmap='viridis', aspect='auto')

# Overlay contours
axes.contour(data, levels=np.linspace(10, 60, 6), colors='yellow', alpha=0.5)
axes.set_title('SANSLOQCan2D.nxs')
cbar=fig.colorbar(c)
cbar.set_label('Counts ($\mu s$)$^{-1}$') #add text to colorbar
fig.tight_layout()

fig.show()

crosshair button is back and can be enabled.

In all three scenarios, changing axes scale from linear to log should not cause anything to crash.

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