fix Issue 9198 - Vararg functions don't respect IFTI rules
fix Issue 6905 - ref acts as auto ref when return type is missing
drop 'www.' from dlang.org urls
switch ddoc references from digitalmars to dlang
fix up file header comment

1) drop obsolete links to dsource
2) drop path to backendlicense.txt
3) update readme.txt to point to dlang.org
Fixes Issue 9250 - Wrong line number in assignment diagnostic
Merge pull request #1433 from AndrejMitrovic/Fix9250_2

Issue 9250 - Wrong line number in assignment diagnostic
no more calls to __DBLULLNG
eliminate need for __DBLULNG
eliminate need for __LDBLULLNG
Merge branch 'master' of github.com:D-Programming-Language/dmd
forgot code.h
set STACKALIGN for all targets
no longer need 2 passes
fix Issue 9268 - [ice-on-invalid] void assignment in fail44.d no longer caught in frontend
Add "Internal error: ..." check
Fixes Issue 9191 - Wrong diagnostic on failing override.

For failing overrides the compiler should look for similar symbols in the
base classes and interfaces, and not the current class.
Merge pull request #1436 from AndrejMitrovic/Fix9191

Issue 9191 - Wrong diagnostic on failing override
Merge pull request #1434 from 9rnsr/fix9268

Issue 9268 - [ice-on-invalid] void assignment in fail44.d no longer caught in frontend
refactor; remove use of SCtmp