Kill introduced again deprecated `WEB` macro.

This is a fixup for pull request #349.
Fix issue 11001 - Add documentation for __traits(getVirtualIndex).
Merge pull request #378 from Kapps/fix11001

Fix issue 11001 - Add documentation for __traits(getVirtualIndex).
add link to core_demangle.html
Merge pull request #379 from dawgfoto/addCoreDemangle

add link to core_demangle.html
Fixes Issue 11035 - Document lack of .stringof reliability.
Merge pull request #380 from AndrejMitrovic/Fix11036

Issue 11035 - Document lack of .stringof reliability.
Merge pull request #363 from denis-sh/fixup-pull-349

Kill introduced again deprecated `WEB` macro.
Added resource files needed by the ddox generated API docs.
Add necessary files and build targets to generate API docs using the dpl-docs generator.
Tweak CSS style of the new API docs.
Remove entries for deleted Phobos modules.
Remove "register" as a D keyword in the syntax highlighting script.
Improve style of get/set annotations and make anchors in headers less bold.
Add a "apidocs" target in win32.mak to generate API documentation using dpl-docs.
Add a win32 make target for HTTP serving the API documentation locally instead of generating HTML files.
Add indicators for inherited class members and the protection level of symbols.
Add newline before EOF.
Remove redundant macro definitions in std-ddox.ddoc and add an "apidocs-serve" target in posix.mak.
Let win32.mak generate the list of needed source files for the apidocs targets on the fly.

api-docs-files.txt isn't needed anymore on Windows.