Merge branch 'master' into test_opt
Merge branch 'test_opt' of https://github.com/neuropoly/spinalcordtoolbox into test_opt
TEST: missing tests added
OPT: removed possibility to input transformation matrix to avoid potential conflicts with the 2-stage registration
OPT: sct_register_multimodal: major changes. Now using sliceReg
OPT: added interpolation flag
OPT: sct_extract_metric: now possible to specify slices (not only range)
BUG: sct_extract_metric: fixed bug related to saving text file
BUG: forgot debug mode
OPT: now possible to input inversed matrix
OPT: now possible to output dest2src and associated transformation
REF: removed possibility to set flag for compute_dest2src
OPT: sct_antsSliceRegularizedRegistration now outputs inverse warping
OPT: removed flag for number of iterations in register_multimodal (less confusing for user)
BUG: fixed bug
BUG: fixed bug
Merge branch 'test_opt' into jca_regMultimodalUsingsliceReg

Conflicts:
	testing/test_all.py
OPT: changed default z gap from 2 to 15
Merge branch 'augustin' of github.com:neuropoly/spinalcordtoolbox into jca_regMultimodalUsingsliceReg

Conflicts:
	scripts/sct_straighten_spinalcord.py
Merge branch 'augustin' of github.com:neuropoly/spinalcordtoolbox into jca_regMultimodalUsingsliceReg

Conflicts:
	scripts/sct_straighten_spinalcord.py