Add allocator support to StringMaker<vector>

 - also extracted out 'rangeToString', in an attempt to make it easier
   to add support for other containers
catch_tostring : moved defintion of rangeToString

 Detail::rangeToString is now defined after the various toString
overloads. This results in them being accessible with rangeToString is
instantiated (in this case, by StringMaker<vector>). This (sort-of)
fixes the problem where contained types are toString'd incorrectly.

Consider:
  std::vector<std::string> v { "abc" };

Before:
  Catch::toString( v ) == "{ abc }"
After:
  Catch::toString( v ) == "{ "abc" }"

(note the extra pair of quotes around the "abc" - these are added by
Catch::toString( std::string ) which is now called by rangeToString)
updated single-include version
Eliminate a warning in the latest clang with Xcode
Upgraded project for latest Xcode
Fix for comma separated tags on the command line
- also added more test for tags
Merge pull request #198 from PureAbstract/vector_to_string

Add allocator support to StringMaker<vector>
Merge commit '22ded1f2bb3caf96d90c2f1981ede29d3aeb1c74'
Removed outdated Xcode 3 project
Split approve file into multiple files
Trim paths in approval tests down to filenames
No, really trim paths in approval tests down to just filenames
Filter out version number from approval tests
Expanded docs on tests cases and sections (still work-in-progress)
- also touched up some outdated bits in the tutorial
Expanded test-cases-and-exceptions docs and added to reference-index
escaped square brackets
minor doc tweaks
Fix wrapping width when listing tests
- addresses #201
Added VS2013 (RC) test project