Integrate apphelp

apphelp should be integrated in:

• process creation (LDR).
• COM
• msi
• Driver loading

For this, we need documentation / an implementation.
The LDR part is already somewhat documented in reactos: (https://git.reactos.org/?p=reactos.git&a=search&h=HEAD&st=grep&s=Shim+Engine), the rest is not.