Add package libwebp

See #442 and #445.

Signed-off-by: Timothy Gu <timothygu99@gmail.com>
gdk-pixbuf: install files when autoreconfing

Might fix #451.
update package openssl
libwebp: build all libraries

Signed-off-by: Timothy Gu <timothygu99@gmail.com>
Merge branch 'master' of https://github.com/mxe/mxe
Reduce difference with master

Signed-off-by: Timothy Gu <timothygu99@gmail.com>
Merge branch 'stable'