Merge branch 'release-1.1'
Drop sixel_image_t object and related functions
Merge branch 'develop' of github.com:saitoha/libsixel into develop
Change the behavior of sixel_dither_set_diffusion_type, improvement for sdump.
Print short usage explanation if invalid option is given.
Issue #7: correct wrong CLEANFILES definition
Issue #7: Add test.log to CLEANFILES
Issue #7: prevent to erase package.json in "make distclean" target
Update .gitignore
Merge branch 'master' into release-1.1
Merge branch 'option-help-to-stdout' into release-1.1

Conflicts:
	src/image.c
Bump version
Merge branch 'fix-issue-7' into release-1.1
Merge branch 'feature-autoselect-diffusioin-type' into release-1.1