Make Tuple.opAssign CTFEable
Detab and strip std.bitmanip.
Space after if
Merge pull request #1325 from youkei/fix_10218

Issue 10218 - std.typecons.opAssign is not CTFEable
Fixes Issue 4124 - Implement toString for BitArray.
Merge pull request #1144 from AndrejMitrovic/Fix4124

Issue 4124 - Implement toString for BitArray.