fix #19, tutorial update pycall (ex10)

[jmorice91]

No description provided.

[JAuriac]

Suggested change

	#*** the name of the PDI variable to write.
	#...
	dataset: main_field # name of the dataset in "ex10.h5"
	dataset_selection:
	size: [1, '$dsize[0]-2', '$dsize[1]-2']
	start: ['$ii-1', '$pcoord[0]*($dsize[0]-2)', '$pcoord[1]*($dsize[1]-2)']
	#*** load the pycall plugin and enable this plugin for event loop.
	#...
	#*** Specifies the input parameters (variables) to pass to Python as a set of "$-expressions" (expressions must be defined in .yml script)
	#...
	#*** add exec keyword of pycall plugin. Decomment and the following python script
	#...
	# import numpy as np
	# if 0 < iter_id < 4: # iter_id: time iteration
	# transformed_field = np.sqrt(source_field[1:-1,1:-1])
	# pdi.expose('transformed_field', transformed_field, pdi.OUT)
	## Comment: The last line allows to expose transformed field to PDI. Hence, the data is known by PDI in this call.
	#*** the name of the PDI variable to write
	#...
	dataset: main_field # name of the dataset in "ex10.h5"
	dataset_selection:
	size: [1, '$dsize[0]-2', '$dsize[1]-2']
	start: ['$ii-1', '$pcoord[0]*($dsize[0]-2)', '$pcoord[1]*($dsize[1]-2)']
	#*** load the pycall plugin and enable this plugin for event loop
	#...
	#*** specifies the input parameters (variables) to pass to Python as a set of "$-expressions" (expressions must be defined in .yml script)
	#...
	#*** add exec keyword of pycall plugin. Decomment and the following python script
	#...
	# import numpy as np
	# if 0 < iter_id < 4: # iter_id: time iteration
	# transformed_field = np.sqrt(source_field[1:-1,1:-1])
	# pdi.expose('transformed_field', transformed_field, pdi.OUT)
	## Comment: The last line allows to expose transformed field to PDI. Hence, the data is known by PDI in this call.

Need to unify comment format for all files. As of now, some comments got no uppercase and no end dot, some only get the uppercase (as in ex10.c), and some have both.
Also need to modify to account for solution's indent (transformed_data).