Merge pull request #84 from iamleeg/master

Comparison between signed and unsigned
Context methods are non-static - accessed via interface

This is a move towards allowing multiple contexts - with the concept of a (possibly thread local) "current" context
Added support for Objective-C exceptions
Merge branch 'master' of github.com:philsquared/Catch
Removed "singleton" method from context

There is now a global "currentContext" - but Context itself is not aware of it
Added a delta method to Totals that tracks new passed/ failures

This fixes issue with test group results
Regenerated single include
Reinstated #include that broke single include
single header now includes date-time of generation in comment header
Silence "unused parameter" warning.
Renamed VisualStudio to VS2008
Added VS2010
Updated gitignore
Fixed GitHub Issue #90
Fixed some warnings
Removed special handling for pointer comparisons

These all seem to be handled by the general case now
Added Equals matcher for strings
Matchers macro uses Catch::Matchers namespace internally - so it doesn't have to be declared with "using" first
Regenerated single include
Added evaluator overloads for case when comparing pointers against NULLs that decay to ints