Added option to convolve to conv fit

Refs #8802
Merge branch 'master' into feature/8802_convolve_option_for_conv_fit

Conflicts:
	Code/Mantid/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/IndirectDataAnalysis.ui

Refs #8802
Move convolve option to property tree

Refs #8802
Merge branch 'feature/8802_convolve_option_for_conv_fit' into develop