Update apache::params for Amazon Linux

Amazon Linux AMI is a lot like RedHat 6 but has an
`$operatingsystemrelease` value of `3.4.37-40.44.amzn1.x86_64`
currently which throws off the `$distrelease` in the params class.

Adding these defaults should fix this issue.
Merge pull request #288 from hunner/update_amazon

Update apache::params for Amazon Linux
add auth template that is a bit more general

Directives:

* auth_type
* auth_name
* auth_digest_algorithm
* auth_digest_domain
* auth_digest_nonce_lifetime
* auth_digest_provider
* auth_digest_qop
* auth_digest_shmem_size
* auth_basic_authoritative
* auth_basic_fake
* auth_basic_provider
* auth_user_file
* auth_require

This patch is still incomplete. E.g. directives for authentication providers and
authorization are missing.
remove obsolete documenation for auth_basic_file
use puppet syntax highlighting in README.md
add documentation for auth* directives
remove template nesting (does not work)
Merge pull request #289 from booo/auth

Auth
add custom_fragment attribute to directories hash
document the custom_fragment option for directory hashes
Merge pull request #290 from booo/custom_fragment

Custom fragment
Allow configuration of WSGISocketPrefix for mod_wsgi
Add spec test for custom WSGISocketPrefix
Merge pull request #296 from stdietrich/add_wsgi_socket_prefix

Allow configuration of WSGISocketPrefix