fix issue 13163 - std.conv.parse misses overflow when it doesn't result in a smaller value
don't bother with signed types

Everything is >= 0 all the time anyway.
fix whitespace
Define isNaN deprecation for integers

Also cleans isNaN unit tests
Add more integer isXXX deprecations

Also implementation is changed to forward to floating point signature
instead of a stub to exactly match old behaviour.
Add missing imports
fix property enforcement
Made File.writeln infer @safe/@trusted/etc. Also wrapped stdout in @trusted private function so writeln (and family) free functions don't always infer @system.
Merge pull request #2233 from rbanderton/fix-writeln-inference

Fix Issue 6644 - std.stdio write/writef(ln) are not @trusted
Merge pull request #2355 from NilsBossung/13163

fix issue 13163 - std.conv.parse misses overflow when it doesn't result in a smaller value
Mark unittests for std.file.readText, rename and exists as safe
Merge pull request #2383 from tom-tan/safe-unittests-for-file-readText-etc

Mark unittests for std.file.readText, rename and exists as safe
fixup #2377 - add back missing $(SONAME) symlink
Merge pull request #2387 from MartinNowak/fixup2377

fixup #2377 - add back missing $(SONAME) symlink
Issue 13232 - avoid expensive template instantiations on module import

- hide std.uni.TrieBuilder instantiations behind functions
Merge pull request #2389 from 9rnsr/fix12359

Add missing imports
Merge pull request #2392 from MartinNowak/fix13232

Issue 13232 - avoid expensive template instantiations on module import
Remove workaround for issue 12164.
localize some imports
Merge pull request #2374 from Dicebot/nan-deprecation

[reg] isNaN deprecation for integers