mantidplot dir renamed to pymantidplot, avoid name conflict, re #8912
update doc and tests to pymantidplot, avoid name conflict, re #8912
Merge branch 'feature/8912_CLI_new_branch_to_solve_conflicts' into develop

Conflicts:
	Code/Mantid/MantidPlot/CMakeLists.txt

Usual conflict with mantidplot / pymantidplot names and indents, re #8912