Add a basic ansible-pull man page.

Add the example playbooks/scripts to the RPM package.

Closes #841

Always load group_vars and host_vars.

Further fixes for constants following config introduction

Added an ANSIBLE_CONFIG variable to poteentially override
~/.ansible.cfg
Used os.path.expanduser against all paths that might be read in to allow
~ to be used in config files. I'd have preferred it if os.path.expanduser
took None as an argument but it doesn't.

If remote_port *is* set in the ansible config file, then it will be
interpreted as a string (at which point ssh.connect fails with an
obscure message). Most other numeric variables are handled by
the OptionsParser which takes a type variable when setting up the option -
but remote_port is not an option, so never cast to int.

It might be worth adding a type field to get_config that defaults to a string.
That could be e.g. file or int, which then casts it correctly.

Bugfix/apt repository

fixed missing module argument for mount module

Use Python 2.4 compatible syntax

A couple fixes for setup module

If ip is not found in either /sbin or /usr/sbin, this will return
an empty result.  It seems extremely unlikely that a linux system will
not have iproute2 installed

Specify full path to ip and add third argument 'show' to be explicit
about requested action.  This goes from 'ip addr' to
'/sbin/ip addr show'.

Add module common code to allow it to be easier to indicate whether arguments are mutually exclusive, required in conjunction, or whether one of a list of arguments is required.  This simplifies writing Python modules.

Make pep8 tests run against the library directory as well, and associated tweaks (mostly to indentation) in the library
directory.

Add openvz detection to virtualization facts, and some cleanup

Remove tests that involve network effects -- makes things faster and they are not really deep tests here either way.