* fix issue #9228 : Add support to subgroups in gitlab

* Update vcpkg_from_gitlab.cmake

* Update vcpkg_from_gitlab.cmake

* [portfile functions] Override execute_process() to accept ALLOW_IN_DOWNLOAD_MODE option

* [vcpkg install] Set VCPKG_DOWNLOAD_MODE when using --only-downloads option

* [vcpkg_find_acquire_program] Allow in Download Mode

* Don't stop when build fails for a package

* Download sources for all packages in dependency graph

* Improve output messages

* Enable acquiring MSYS packages in download mode

* Documentation

* Update documentation

* execute_process() always fails on Download Mode

* Regenerate docs and fix formatting

* Run clang-format

* Use _execute_process on vcpkg_from_<source> helpers

* Fix calls to _execute_process() when not in Download Mode

This reverts commit 65d4bc146bf7c1c21989b680497b1f6f9a09c967.

* [portfile functions] Override execute_process() to accept ALLOW_IN_DOWNLOAD_MODE option

* [vcpkg install] Set VCPKG_DOWNLOAD_MODE when using --only-downloads option

* [vcpkg_find_acquire_program] Allow in Download Mode

* Don't stop when build fails for a package

* Download sources for all packages in dependency graph

* Improve output messages

* Enable acquiring MSYS packages in download mode

* Documentation

* Update documentation

* execute_process() always fails on Download Mode

* Regenerate docs and fix formatting

* Run clang-format

* Use _execute_process on vcpkg_from_<source> helpers

* Add headers to vcpkg_download_distfile

Allows headers to be appended when downloading a distribution. This allows for setting
authentication headers to download from a private repository.

* [scripts,docs] Regenerate docs for portfile functions

* [docs,scripts] Fix typo regressions

* [docs,scripts] Fix broken link

* [GraphicsMagick] bug-fix: image files won't load

GM (GraphicsMagick) was failing to load image files, notably PNG or JPEG
images, as it was being compiled with support for 'GraphicsMagick
Modules'.  These are files with names specific to GM, and of the format,
'IM_*.dll'.  vcpkg's install process was not setting these up.  This
patch makes sure that when GM is built, it embed's GM's own
image-loading code into graphicsmagick.dll.

* [vcpkg_extract_source_archive_ex] Add PATCHES argument

* [openmesh] Use direct download instead of gitlab

* [blaze] Use PATCHES argument

* [graphicsmagick] Use vcpkg_extract_source_archive_ex