Make std.string.removechars @safe and pure
Make std.string.removechars @safe and pure by using implicit conversion
Add RefRange to ddoc overview.
Merge pull request #1520 from tom-tan/safe-pure-string-removechars

Make std.string.removechars @safe and pure
Merge pull request #1522 from quickfur/issue10885

Add RefRange to ddoc overview (issue 10885)