Split up rt.util.container module into package.
Add xmalloc and use it in HashTab.get(key)
make ModuleInfo immutable

- allows to put them into read-only segment and
  avoid some copy relocations

- use allocated bit vector for module sorting

- also mark all ModuleInfo methods and members as const
fix for Issue 11543 - multiple definition of std.regex with shared library

- Detect copy relocated ModuleInfos when checking for
  conflicting module definitions.
Merge pull request #790 from MartinNowak/immutableModuleInfo

make ModuleInfo immutable
back GC.add/remove Root/Range with treap instead of unsorted array.
Try to address feedback comments and build issues.
fix property enforcement
Merge pull request #792 from 9rnsr/enforceProp

fix property enforcement
Merge pull request #788 from Safety0ff/gctreap

[Prototype] GC.add/remove Root/Range using treap instead of unsorted array.
@nogc cpuid
Merge pull request #793 from WalterBright/annotate-cpuid

@nogc cpuid
core.sys.posix: annotate
Merge pull request #794 from WalterBright/posix-annotate

core.sys.posix: annotate
Only define vector aliases if they actually compile
Merge pull request #795 from yebblies/issue8425

Only define vector aliases if they actually compile
Add enhanced unittest runtime information

The new information is available from the 'unitTests' member of
every ModuleInfo.
'unitTests' is an array of __UnitTest structs. The __UnitTest
struct provides the unittest function, location etc.
Use new unittest format in default runner
Support named unittests
Fix cache inconsistency when free'ing from GC

After a pointer is freed, it is not removed from cache thus if it is allocated for another purpose any subsequent realloc calls will refer to the previous size.

This can cause memory corruption with an application that uses `GC.free`, `delete` or `realloc(p, 0)`, or a complete crash if a big allocation's size is cached and the page pool was reduced with minimize, ie. the call to `realloc` will try to resize in-place rather than with malloc.

Verify USE_CACHE at compile-time

Fix alignment
Fixed some signed/unsigned warnings in druntime