preserve path to object file in COFF library to avoid ambiguities
Fixes Issue 8922 - __traits(parent) should fail on top package import
fix Issue 8631 - illegal overrides accepted
[trivial] There is no 'final struct variable'.

The code don't have meanings anymore in D2.
Refactoring semanticTiargs
fix Issue 9178 - UDA: getAttributes does not play well with tupleof
Refactoring semanticTiargs more

Standardize processing of tiarg - type, symbol, and expression.
remove bt() builtin
Merge pull request #1510 from WalterBright/b14

remove bt() builtin
isolate dmd from dt internals
Merge pull request #1511 from WalterBright/b16

isolate dmd from dt internals
Merge pull request #1504 from 9rnsr/refactor

[trivial] There is no 'final struct variable'.
Merge pull request #1505 from 9rnsr/refactor_tiargs

Refactor semanticTiargs() and fix Issue 9178 - UDA: getAttributes does not play well with tupleof
Merge pull request #1455 from AndrejMitrovic/Fix8922

Issue 8922 - __traits(parent) should fail on top package import
Merge pull request #1450 from 9rnsr/fix8631

Issue 8631 - illegal overrides accepted
Merge pull request #1315 from rainers/keep_mscoff_path_in_lib

preserve path to object file in COFF library to avoid ambiguities