Allow Apache service not to be managed by Puppet

Currently Apache can either configured to be 'running' or 'stopped'. In our cluster setup Apache is managed by Pacemaker, so Puppet should not interfere. Setting ensure to 'UNSET' will now set ensure to undef for the Apache service.
The apache class now accepts true, false, 'running' or 'stopped' for the parameter service_ensure. Any other value wil result in the parameter 'ensure' for the Apache service being set to undef.
Whoops
Added WSGIPassAuthorization option to vhost.
Added The ProxyPreserveHost option to vhosts.
Updated readme with WSGIPassAuthorization information, updated spec and
rspec tests for WSGIPassAuthorization.
added documentation and test for ProxyPreserveHost option
Merge pull request #694 from Conzar/master

Added WSGIPassAuthorization option to vhost.
Merge pull request #690 from arnoudj/master

Allow Apache service not to be managed by Puppet
(MODULES-910) Convert @apache_version to a string

Three part version numbers cannot be floats and must
be represented as strings. This commit changes all instances
of $apache_version and any comparsions to use strings and the
versioncmp function.

This also fixes comparsion of Float and String errors with future
parser enabled.
Merge pull request #731 from blkperl/convert_versions_to_string

(MODULES-910) Convert @apache_version to a string
MODULES-956 Added loadfile_name parameter to apache::mod.

This will allow for more control over the module load order, since
they appear to be loaded alphabetically.
Update README.md

Add http:// protocol to URLs referring to Apache web site so that markdown processor doesn't think that they are relative URLs.
Merge pull request #737 from mhaskel/rename_mod_load

MODULES-956 Added loadfile_name parameter to apache::mod.
Renamed file resource to use loadfile_name if provided.
Merge pull request #746 from mhaskel/rename_mod_load

Renamed file resource to use loadfile_name if provided.
Add support for SVN authentication (mod_authz_svn)

Add dependency for authz_svn. This is needed, since the mod is included in the dav_svn system package. Thanks @hunner for pointing this out!

- Add parameter for controling the enabl-/disabling of the authz_svn module. (Disabled by default)
- Optimize the dependency management

Mark dav_svn module as a module which has optional setings.

Add loadfile_name parameter for better module load order

Add acceptance test for dav_svn module
Merge pull request #696 from baurmatt/master

Added support for SVN authentication (mod_authz_svn)
Merge pull request #738 from kgeis/patch-1

Update README.md
Merge branch 'master' of https://github.com/puppetlabs/puppetlabs-apache