Merge pull request #3613 from WalterBright/hpohl-opt

Increase allocation chunk size + minor refactoring
Merge pull request #3745 from economicmodeling/coverage_test_case

Added test case for druntime pull request 830.
Merge pull request #3746 from Safety0ff/test7068

Add regression test for bug 7068.
Merge pull request #3737 from 9rnsr/fix11066

Issue 11066 - Spurious warning 'statement is not reachable' with -profile
Merge pull request #3734 from 9rnsr/fix13082

Issue 13082 - Spurious error message with failed call to class ctor
Merge pull request #3751 from lionello/fix13109

Issue 13109 - Show error on conflicting args -lib and -run
Merge pull request #3764 from 9rnsr/fix13131

Issue 13131 - [2.066-b3] dmd: glue.c:1492: unsigned int totym(Type*): Assertion `0' failed.
Merge pull request #3750 from Trass3r/master

use enums
Merge pull request #3749 from yebblies/valistfix

[DDMD] Remove extern "C" verror hacks now that va_list has been fixed
Merge pull request #3770 from yebblies/gluector

[DDMD] Do not call constructors from the glue layer (lib*)
Merge pull request #3772 from yebblies/linesplice

[DDMD] Remove unnecessary line splicing in clone.c
Merge pull request #3771 from yebblies/signext

[DDMD] Make construction of SignExtendedNumber explicit
Merge pull request #3769 from yebblies/DDMDMOD

[DDMD] Use explicit MOD type to avoid narrowing conversions from unsigned int
Merge pull request #3768 from yebblies/paintAsTypeddmd

[DDMD] Make narrowing cast explicit
Merge pull request #3767 from yebblies/ddmdcolor

[DDMD] Make color ddmd-friendly
Merge pull request #3763 from 9rnsr/fix13127

[REG2.066a] Issue 13127 - Cannot deduce function with int[][] argument and "in" parameter
Merge pull request #3774 from 9rnsr/2.066

Cherry-picking commits from master to 2.066 branch (for beta5)