fix Issue 13746 - formatValue of delegates
Document new idiom for using Flag.
Merge pull request #2745 from 9il/fv

fix Issue 13746 - formatValue of delegates
Merge pull request #2741 from quickfur/flag

Document new idiom for using Flag.
std.conv.d - Fix typo
Merge pull request #2748 from JinShil/patch-1

std.conv.d - Fix typo
Add the capability to create tagged pointer and classes in bitmanip
fix constness of some char*
fix property enforcement
Add missing imports
Merge pull request #2749 from MartinNowak/curl

fix constness of some char*
Merge pull request #2752 from 9rnsr/fix_imports

Add missing imports
Merge pull request #2751 from 9rnsr/enforceProp

fix property enforcement
isNaN() is not a property

...so it shouldn't be used as one.
std.typecons: remake toString to template, clean module imports

update datetime unittests
avoid triggering issue 13745 in further improvements to come
Merge pull request #2753 from kyllingstad/isnan-notaproperty

isNaN() is not a property
clean scope imports

imports of `std.range, std.algorithm, std.array, std.string,
std.format, std.uni` are affected.
Merge pull request #2728 from 9il/typecons

std.typecons: remake toString to template, clean module imports
std.random: update imports