DOC: improved docstring
EHN: from fraction to weight
EHN: a2w and w2a multicrimension
EHN: multi dimenstion density
EHN: short cut for a2w w2a
EHN: add tests
EHN: doc
EHN: Docstring
Merge branch 'EHN_w2a_a2w_dens_image' into edslab

Conflicts:
	hyperspy/_signals/eds.py
	hyperspy/misc/material.py
	hyperspy/tests/utils/test_material.py
EHN: doc
EHN: accept list of signals
EHN: elements = 'auto' for list of signals containing elements
EHN: add line and elements in result of get_lines_intensity
EHN: lines and elements in metadata result
SUP: shortcut in eds (redundant)
EHN: add composition_units for Cliff Lorimer
Merge branch 'EHN_get_line_intensity_results' into edslab

Conflicts:
	hyperspy/_signals/eds.py
SUPP: comment dev get_lines_intens. Use the one of maste
Merge branch 'EHN_w2a_a2w_dens_image' into edslab

Conflicts:
	hyperspy/_signals/eds.py
	hyperspy/misc/material.py
	hyperspy/tests/utils/test_material.py
EHN: improvements from francisco-dlp suggestion