d: Merge upstream dmd 817610b16d, phobos b578dfad9

D front-end changes:

    - Import latest bug fixes to mainline.

Phobos changes:

    - Import latest bug fixes to mainline.
    - std.logger module has been moved out of experimental.
    - Removed std.experimental.typecons module.

gcc/d/ChangeLog:

	* dmd/MERGE: Merge upstream dmd 817610b16d.
	* d-ctfloat.cc (CTFloat::parse): Update for new front-end interface.
	* d-lang.cc (d_parse_file): Likewise.
	* expr.cc (ExprVisitor::visit (AssignExp *)): Remove handling of array
	assignments to non-trivial static and dynamic arrays.
	* runtime.def (ARRAYASSIGN): Remove.
	(ARRAYASSIGN_L): Remove.
	(ARRAYASSIGN_R): Remove.

libphobos/ChangeLog:

	* libdruntime/MERGE: Merge upstream druntime 817610b16d.
	* libdruntime/Makefile.am (DRUNTIME_DSOURCES): Add
	core/internal/array/arrayassign.d.
	* libdruntime/Makefile.in: Regenerate.
	* src/MERGE: Merge upstream phobos b578dfad9.
	* src/Makefile.am (PHOBOS_DSOURCES): Remove
	std/experimental/typecons.d. Add std/logger package.
	* src/Makefile.in: Regenerate.