[Refactoring] Remove goto jumps
fix Issue 11888 - Incorrect behaviour taking slice from return value
fix Issue 12979 - Nothrow violation error is hidden by inline assembler

- deprecate using unattributed asm in attributed functions

- add explicit attributes on asm statments (unverified by compiler)

  asm pure nothrow @nogc @trusted {
    //...
  }

- added new CompoundAsmStatement because the parser
  already splits asm blocks into many AsmStatements
[Refactoring] Reorder function declarations
Check redundant/conflicting attributes more
Check invalid syntax and redundancy on static constructors

Improve diagnostic for issue 6677.
Set prefix attributes in storage_class of (Unittest|New|Delete)Declaration

Partially fix issue 8081.
Merge pull request #4044 from 9rnsr/fix_parse

Improve parsing issues around attributes
Merge pull request #4026 from 9rnsr/fix11888

Issue 11888 - Incorrect behaviour taking slice from return value
wording of error messages
Merge pull request #4033 from MartinNowak/fix12979

fix Issue 12979 - Nothrow violation error is hidden by inline assembler
fix Issue 13574 - incorrect code for assignment to dollar in slice expression
Merge pull request #4045 from 9rnsr/fix13574

Issue 13574 - incorrect code for assignment to dollar in slice expression