Merge branch 'develop' into build
Build with extra waning flags
Fix overflow issue in sixel_decode
Suppress sign-compare and unused-parameter warnings by clang
Add dummy members to some structs in sixel.h because empty struct is a GNU extension
Strip an extra conditional clause
Strip an extra conditional directive
Strip an unused local variable
Suppress an -Wsigned error in converters/stb_image.h
Make PNG loader using libpng as a separated function
Don't use setjmp for the future because it's thread-unsafe
Revert "Fix overflow issue in sixel_decode"

This reverts commit 0ae94a3e6fcfc574c7a32fc3e9c80594de4d778b.
Get rid of unused variables
Merge branch 'develop' of github.com:saitoha/libsixel into develop
Fix a maybe-uninitialized GCC warning
Merge pull request #16 from saitoha/arakiken

Optimize encoding to sixel sequence.
Add missing options in manpage
Add a test for avoid forgetting to write about new options in manpage
Merge branch 'develop' of github.com:saitoha/libsixel into develop
Add the explanation of -E option to manpage