Fix bug 7648 comment in `std.stdio.File` and add bug section to `std.file.slurp`.

Issue URL: http://d.puremagic.com/issues/show_bug.cgi?id=7648
Fix Issue 12556 - Add persistent byLine
Make byLineCopy support mutable line copies
Fix caching byLineCopy.front (oops)
std.math: Check if dmd-style inline asm is available
Issue 10194. Variant does not call struct destructors.
Implemented elaborate copying support.
Sanitize Appender constraints a bit.
Clarify when to use byLineCopy vs byLine
New Container

Turn std.container into a package.

Delete container.d

Remove totalcontainer from package.
Create std.container.util.d and reference it from other containers.
Correct code coverage for containers.

Add containers for unit testing.

Make std.container.util public from any module.
Move around imports (avoid version(unittest)).

Remove irrelevant unittests.
Fix issue 3363: std.stream.readf segfaults with immutabel format strings
Make std.stdio.LockingTextWriter.put and lockingTextWriter @safe
Update to git head.
Merge totalcontainer.d with package.d
Fix #12806

Documentation improvement for `std.traits.isArray` to clarify whether
associative arrays are handled.

Fixes #12806
Reuse codepoint sets for identical character classes

These are very common and blowup memory usage at CTFE (that has no TLS
cache for that).
In any case it makes for slightly more compact memory footprint,
so a net gain regardless.
Fix Issue #12877: allow uniform() to handle dchar variates

Since [dchar.min, dchar.max] does not cover the full bit range of dchar,
optimizations that work for other integral types will fail here, and
result in illegal unicode points being generated.

This fix avoids breaking any existing calls to uniform() via a twofold
approach:

   * uniform!"[]"(T.min, T.max) will only call uniform!ResultType if
     T is not a dchar;

   * uniform!dchar will not try and use the entire bit range but will
     instead call uniform!"[]"(dchar.min, dchar.max).

Unittests have been added that should prevent such issues from arising
again.
Merge pull request #2234 from DmitryOlshansky/regex-reuse-sets

std.regex - reuse codepoint sets for identical character classes
Merge pull request #2231 from economicmodeling/fix_12806

Fix #12806
Make trustedFwrite static