Enable running against iOS SDK 6.1 in CI
Disable running against iOS SDK 5.1 in CI
Merge pull request #68 from xoebus/travis-ios-61

Enable running against iOS SDK 6.1 in CI
Spying on nil now throws an obvious exception
Implement -[CedarApplicationDelegate window]

- It throws an exception informing the user that s?he is not actually asking
  h(er|is) own app's delegate for the window.
- Stubbing is suggested to reveal intent in tests more clearly.
Updated README sections about matchers and ARC
Fix retaining args of recorded invocations

- Only arguments (not the receiver) are retained now
- Block arguments are copied so they won't be garbage if the stack
  they're created in is destroyed.
- Copied blocks are released when the double is released
- c-strings are also copied
- sent_messages NSInvocations returns copied blocks/c-strings from
  getArgument:atIndex:
Moved header file
Fix allocation when copying NSInvocation C strings

- strlen() didn't account for the NULL terminator
Release recorded double invocations in afterEach

- Breaks retain cycles which may be created by invocation recording
Minor cleanups
Removed private header from copy headers
Empty describe blocks don't count as examples
Stub arguments can now be specified .with(varargs)

- Finishes [#47205477]
- Fixed issues with argument type matching; Finishes [#48994375]
Methods can be stubbed multiple times

- Arguments must differ from previous stubs
- Multiple stubs on the same method using Arguments::anything or
  Arguments::any is disallowed to avoid ambiguities
- Spies call their default implementation if stub arguments don't match
==/gt/lt/gte/lte matchers support NSDecimalNumbers
==/gt/lt/gte/lte matchers support NSDecimals

Finishes [#33971077]
Exceptions thrown in afterEach are now handled
Install now works from paths containing spaces.
afterEach always runs after example