[vcpkg manifest] Add documentation! (#13488)

* [vcpkg docs] add docs for manifest files

These are just for the maintainer docs,
not user docs.

* [vcpkg] EBNF-ify platform expression parsing

this modifies nothing about what strings are accepted or rejected,
it just moves stuff around.

also adds tests.

* [vcpkg docs] add manifest mode example

* [wip] docs for augustin

also fix tabs

* [vcpkg manifest] switch to using maps for features

* Apply suggestions from code review

* un-experimentize format-manifest

* flesh out the user manifest mode docs

* CRs

* billy CRs

* final personal pass-thru

1 files changed, 1 insertions, 1 deletions

diff --git a/toolsrc/src/vcpkg-test/commands.cpp b/toolsrc/src/vcpkg-test/commands.cpp
index c19fd30ea..38346291c 100644
--- a/toolsrc/src/vcpkg-test/commands.cpp
+++ b/toolsrc/src/vcpkg-test/commands.cpp
@@ -55,11 +55,11 @@ TEST_CASE ("get_available_paths_commands works", "[commands]")
         "autocomplete",
         "hash",
         "fetch",
+        "format-manifest",
         "x-ci-clean",
         "x-history",
         "x-package-info",
         "x-vsinstances",
-        "x-format-manifest",
         });
 }