[boost] [gil] Can I merge two minor fixes to header dependencies and tests for 1.7.4?

Dear Release Manager, I'd like to request permission to merge these two minor fixes into GIL's master for release with 1.74 1. Fix dynamic_image extension header dependencies https://github.com/boostorg/gil/pull/508 This basically removes all-in-one #include <boost/gil.hpp from GIL's own headers. 2. Re-enable self containing header tests in CMake https://github.com/boostorg/gil/pull/509 Minor correction to an incidental disabling of headers tests in CMake. May I? Best regards, -- Mateusz Loskot, http://mateusz.loskot.net