Add std.range.enumerate

Fixes issue 5550
Make std.file.isFile, isSymlink and their unittests safe
Fix trustedSymlink to use toStringz
Improve documentation of std.string.column.
std.path.absolutePath should accept mutable pathnames.
Add unittest for worksforme bug.
Update std.stdio.writef docs.

The docs are outdated; the `writef(stderr, fmt, ...)` syntax is no longer
supported. Also, remove a bunch of really old notes about changes in version
2.006, which are already ancient history. Refer instead to the docs of
std.format.formattedWrite, which are the most up-to-date and accurate docs on
this subject.
Deprecated obsolete module std.typelist.
Fix argument for isSymlink, and fix unittest for it
Merge pull request #2539 from quickfur/issue10683

Add unittest for worksforme bug.
std.traits: Fix missing ) in documentation of isSomeString
Merge pull request #2520 from tom-tan/safe-file-isFile-isSymlink

Make std.file.isFile, isSymlink and their unittests safe
(trivial) (ddoc) more descriptive Typedef doc.

Based on Andrei Alexandrescu's post: http://forum.dlang.org/post/lvj17a$78k$1@digitalmars.com

`MoneyEuros` makes use of the cookie more obvious than `TypeFloat1`.
Merge pull request #2543 from kiith-sa/patch-1

(trivial) (ddoc) more descriptive Typedef doc.
Merge pull request #2537 from quickfur/issue12083

std.path.absolutePath should accept mutable pathnames.
Merge pull request #2541 from quickfur/issue7797

Deprecated obsolete module std.typelist.
Merge pull request #1866 from JakobOvrum/enumerate

Add std.range.enumerate
Merge pull request #2542 from CyberShadow/pull-20140920-071957

std.traits: Fix missing ) in documentation of isSomeString
Revert pull request #2537 to fix git-head regression issue 13498

This reverts commit 875f2fe0314931ef86e597a3d87069c1b914c5bb, reversing
changes made to f5c7e97f2b4ee12e5e486da130ebf69483693bc5.

The changed absolutePath code essentially cannot work because the buildPath() result is not implicitly convertible to inout(char)[], but it was accidentally accepted by the regression 13498.
Merge pull request #2544 from 9rnsr/fix13498

Revert pull request #2537 to fix git-head regression issue 13498