This reverts commit 5f07f7ad.

Removing the legacy code that was replaced by the core.
Also removing the feature flag for core integeration.

auto: increment master version to 17.0.87

docs(windows): link to wiki architecture faq page

auto: increment master version to 17.0.86

fix(ios): fixes xcode-triggered debug, run builds

fix(developer): add DRY_RUN variable to build.sh

chore(developer): AddWarning and SetError cleanup

Fixes #8574.

Also ensures that kmc is published after its dependencies.

auto: increment master version to 17.0.85

* Splits compiler interface functions that return bool into
  CompilerInterfaces.cpp, and moves `SetError` define to that unit so
  it can't be used accidentally elsewhere
* Audit of `AddWarning` calls and only those that are used in bool
  functions now `return FALSE` (with new `AddWarningBool`) whereas all
  others `return CERR_Break`

fix(mac): fix corrupt installer

docs: clarify dependency meanings in build-utils

chore(android): Update projects to use Java 11

Relates to #8542.

epic: kmcompx - kmcmpdll cross-platform compiler 🚑

Because we don't know if mac BSD cp or GNU cp will be first on the path,
where there is ambiguity (e.g. with -R flag), we will use the macOS cp
command in /bin to ensure that we have consistent results. The
alternative would be to fixup each instance of the cp parameters so that
they work consistently with either cp command, but given these scripts
can run only on macOS, that seems unnecessary.

This replaces the earlier change in 97c6331b.

Fixes #8533 after build agent maintenance put GNU coreutils cp on path
ahead of macOS /bin/cp. This subtly changed the behaviour of the `-R`
flag such that it copied the folder into a subfolder rather than copying
the contents of the folder into the destination folder:

Original layout:

```
Install Keyman.app/Contents/MacOS/
  applet
  textinputsource
  Keyman.app/
```

Corrupted layout:

```
Install Keyman.app/Install Keyman.app/Contents/MacOS/
  applet
  textinputsource
  Keyman.app/
```

Query: should we be rolling back the path changes so that /bin is first
on the path? I am concerned about other subtle changes in behaviour in
the macOS and iOS builds. Otherwise it feels like we may need to audit
the scripts in /mac, /ios (and possibly /common, /core, /web,
/resources) for potential changes.

Annoyed that it took me so long. Also annoying that macOS fails so
subtly when a parent folder has the .app extension in its name.

auto: increment master version to 17.0.84

fix(windows): use right instead of left alignment for popup buttons