Add std.range.enumerate

Fixes issue 5550
std.process: Update unittest_burnin to test new functions
std.process: Test random characters at filename start as well
fix Issue 13446 - Can't use executeShell/escapeShellFileName to redirect to file whose name starts with &

Discovered and verified by -version=unittest_burnin
Make std.file.isFile, isSymlink and their unittests safe
Fix trustedSymlink to use toStringz
Fix issue 13483 std.range.tee should accept function symbols
fix Issue 13477 - std.process should ignore unnamed service variables on Windows
issue8851

some more

some review fixes

some more

removed a to
Merge pull request #2533 from burner/issue8851

issue8851
findRoot optimization

restore signbit check

findRoot style update

findRoot style update 2
Merge pull request #2524 from 9il/ctfe-math-2

findRoot optimization and bugfix
Improve documentation of std.string.column.
Merge pull request #2514 from CyberShadow/pull-20140915-022527

fix Issue 13477 - std.process should ignore unnamed service variables on Windows
Merge pull request #2522 from sinkuu/fix_tee

std.range.tee should accept function symbols
Merge pull request #2503 from CyberShadow/pull-20140909-141704

fix Issue 13446 - Can't use executeShell/escapeShellFileName to redirect to file whose name starts with &
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The docs are outdated; the `writef(stderr, fmt, ...)` syntax is no longer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.