add informaction about all pmt
Merge branch 'clew_port_mapping_pmt'

Conflicts:
	app/models/appliance_set.rb
	app/serializers/clew_appliance_instances_serializer.rb
used redis queues amount limited
clew appliance instances serializer spec in correct dir
sidekiq in specific project not in enigine

Engine initializers are executed before RoR application is started.
As a conclusion we are not able to pass any parameter from RoR application
into engine initializer.
coverage report to git ignore
configurable ability class

The main idea is to separate ability model between main application and
atmosphere. If user does not want to extend model and REST interface than
user is not forced to create ability class. Than `Atmosphere::Ability`
will be used. If ability modification are needed than:

1. Ability class should be created e.g.

```ruby
class Ability < Atmosphere::Ability
  ... #additional abilities
end
```

2. Ability class should be set in Atmosphere setup

```ruby
Atmosphere.setup do |config|
  config.ability_class = '::Ability'
end
```
security_proxy_id removed from allowed params
racket removed when possible

Where possible elements like

'''
  :symbol_name => 'value'
'''

was changed into

'''
  symbol_name: 'value'
'''
new validators style used

All old validators like (validates_presence_of) was changed into new rails
style (validates :param_name, presence: true)
basic travis ci configuration
prefer single quotes
codeclimate coverage integration
status badges