Spelling, grammar, layout changes, plus more examples and an orchestration chapter
authorized_key: Be more specific about manage_dir

- Explain which properties are managed when manage_dir is True.
Fix the default url of get_xml function.

* This enable a user to configure uri in get_xml function
Example for queueing build in Jenkins
Update uri
ssh connection plugin: Make comments more verbose

Explain _communicate() more.
Remove extra quote from the mysqldump password argument

The mysqldb Ansible module will fail if the state specified is import or dump with a '1045: Access Denied' mysql error for complex passwords.

This is caused by the extra quote around the '--password' argument to mysqldump, as pipes.quotes already quotes the password string.

>>> "--password='%s'" % pipes.quote('simple')
"--password='simple'"

>>> "--password='%s'" % pipes.quote('c0mplexp@ssword!')
"--password=''c0mplexp@ssword!''"

>>> "--password='%s'" % pipes.quote('password with space')
"--password=''password with space''"
Clarify the port value always defaults to 3306

While the [boto docs](https://github.com/boto/boto/blob/develop/boto/rds/__init__.py#L253) make it seem like the default value of `port` is changed depending on the engine chosen, AFAICT from looking at the code the default value is never changed from 3306.

I think the docs are intended to be read as "the default value used by <engine> is <port> so you should change `port` to that value".

If you don't specify the port value and chose the database engine as PostgreSQL you'll end up with a PostgreSQL instance running on port 3306.
debconf detail requirements and fix typos
debconf correctly quote strings
Fixing some parsing issues in authorized_key module

Also adds an integration test for authorized_key for future validation.

Fixes #6700
Merge pull request #6826 from bob-smith/debconf-parsing

debconf correctly quote strings
Fix issue with sysctl parameter parsing introduced by 0e8c7b1

Fixes #6806
Differentiate decryption failures from empty data files in ansible-vault

Fixes #6822
Fix variable naming issue in _load_tasks()

Fixes #6800
Note that keyserver was added in 1.6
Merge pull request #6770 from lemonlatte/fix_default_uri_of_get_xml

Fix the default url of get_xml function.
Merge pull request #6788 from tyll/pull_ssh_verbose_comments

ssh connection plugin: Make comments more verbose
Merge pull request #6796 from mistaka0s/mysqldump_fix

Remove extra quote from the mysqldump password argument
Merge pull request #6810 from bob-smith/debconf-text

debconf detail requirements and fix typos