* Rename 'BuildRule to 'BuildEdige' because it is the official term
* NinjaParser to handle 'include' and 'rule' directives
* NinjaParser to handle parse "rule name" in 'build' correctly
* Make variable table a simple `[String: String]` and keep any bindings
to make the substitutions possible.
* Generate command line argumets using 'command' variable in the 'rule'
and use it as the source of truth, istead of using random known
bindings like 'FLAGS'.
The intention here was to do a component-wise
prefix check, not sure why I did a string prefix
check. Switch to component prefix and rename to
`starts(with:)` to match `FilePath`.
This requires ensuring we check that we're not
ever attempting to add a group under an existing
folder reference. This will be required for
buildable folders.
This is a tool specifically designed to generate
Xcode projects for the Swift repo (as well as a
couple of adjacent repos such as LLVM and Clang).
It aims to provide a much more user-friendly experience
than the CMake Xcode generation (`build-script --xcode`).
