Removed all sources for starting from scratch.
Added blank project with unit tests.
Added base modules.

- Specification
- Context
- Example
- Hook
Added integrated tests.
Added files for unit testing each module.
Added methods for building examples, contexts and hooks.

Added methods meant for construction to BHVSpecification:
- enterContext:
- leaveContext
- addExample:
- addHook:

These methods are used by DSL to allow clients to construct their specifications.
Use macro for class properties.
Added creation of example invocations.

Algorithm is based on the pseudocode:
```obj-c
Set Context to Parent ContextWhile Context is Not Nil  Add Context Examples to Example List  Add Context Child Contexts to Context Queue  Create an Invocation for each Example  If Context Queue is Not Empty    Pop Context from Context Queue    Set Context to Popped Context  Else    Set Context to Nil  End IfEnd While
```
Added generation of contextual names.

In order to retrieve the example in -name, BHVInvocation has been added, as BHVSpecification depends on it. It is available as part of the public API for testing purposes. Should it be removed?
Made BHVInvocation private to BHVSpecification.
Switched test focus to +testInvocations and -name.

They are the most important functions of the specification unit. This change simplified things greatly – the tests for adding examples and hooks depended on direct access to the class methods +contexts, +examples, and +hooks, but these methods should not need to be made available to the test suite as they are not the primary focus of the tests. The goal of +addExample etc is to make the example available for the creation of an invocation.
Fixed page links.
Move properties to bottom of interface.
Implemented example execution.

Hooks are executed in the following order:
- Before All (before all examples)
- Before Each
- After Each
- After All (after all examples)
Added DSL.

Modified +testInvocations tests to make use of subclasses instead of constructing example structures in each test. This is more awkward, but works from the top of the API (how the client will be using the code) as it should, imo. If we didn't, the number of tests would be astronomical.
Added SpecBegin and SpecEnd macros.
Added Posit for integrated tests, and a few fixes.

DSL needs more unit tests.
Examples and hooks are added to a base context.

Removed `+examples`, `+hooks`, `+contexts` from `BHVSpecification`.
During `+initialize` a base context is added to the stack.
Providing that enterContext and leaveContext calls are balanced, the base context will never be removed.
Fixed order and dependencies of before all hooks.

Execution order is shallowest-to-deepest.
Before All hooks are executed when no example in the __hook's__ context has been.
Updated AfterAll hooks spec.

It is not possible to test afterAll hooks at this level without resorting to manual execution of tests or the use of command-line test invocation using tools such as Cucumber and Aruba. It may be worth resorting to the latter as it provides more flexibility.