Add missing funcsigs package to source release

The vendored funcsigs package was not declared in the setup.py package
defintion so failed to be included in the source distribution.
Prefer __wrapped__ attribute convention

From Python 3.3 the standard library has adopted the convention of
adding a __wrapped__ attribute to wrapper functions with the orginal,
decorated, function. Begins now uses the __wrapped__ attribute rather
than its own convention of the __signature__ attribute for the function
signature of the decorated function.
Add roadmap for beta release of docs

A draft roadmap for features and modifications for begins before it's
ready for a beta release.
Version increment for 0.2 release

Update version number for next PyPI release.
Remove vendored funcsigs package

Stop bundling the funcsigs package within begins and instead declare it
as a dependency on PyPI if required.
Add PyPI version badge to README

Include a badge indicating the most recent version available on PyPI in
the README documentation.
Update changelog for 0.3 release

Mark date 0.2 release was created. Perpare changelog items for comming
0.3 release.
Add basic usage examples to examples collection

Create a new subdirectory below the package documentation to hold the
existing examples as well as add the existing examples already used in
the package README file.
Use argparse internally for command line parsing

Replaces the internal use of optparse in favour of using argparse for
command line parsing.
Fix applying command line to keyword only args

Correct typo in applying command line arguments to keyword only options.
Add unittest to test this line of code.
Fix annotations on variable positional args

The help string for command line arguments created for variable
positional arguments was incorrect. The arguments can not have default
values. Add unit tests to identify these errors.
Make environment variable processing optional

Passing an environment prefix to begin.start() through the env_prefix is
now required to use environment variables to override the default values
of command line options. The previous behaviour was to default to use an
empty prefix.
Update version and CHANGELOG for 0.3 release

Increment version to 0.3 and record date of release in CHANGELOG file.
Fix typo in package README file

Fix invalid RST back reference caused by missspelt word.
Add .PHONY target to Makefile

The .PHONY target prevents make from getting confused if a conflict
happens to exist between the makefile targets and files in the
repository.
Add base class for command line extensions

All command line extensions are expected to inherit from this base
class.
Rename Bottle and Flask example applications

Both this examples derive from the quickstart examples from their
respective framework's documentation. The suffix on the program name has
been changed to reflect this.
Add command line extension for cgitb module

The begin.tracebacks decorator extends the command line parser with an
argument group for configuring the cgitb module to generate enhanced
reports on uncaught exceptions.
Add command line extension for logging module

The begin.logging decorator extends the command line parser with
additional optional arguments and arguments group for configuring the
logging module.
Add missing __all__ variable

Restrict names which are imported by 'import *' using a __all__
variable.