'general_logbooks#index' to display number of logbooks after filtration

app/assets/stylesheets/style.css
- Rename 'div#pagination' and 'div#pagination .current' to
  '#pagination' and '#pagination .current', respectively
app/controllers/general_logbooks_controller.rb
- Modify index() to prepare @num_logbooks.
app/views/general_logbooks/index.html.erb
- Display @num_logbooks.
config/locales/ja.yml
- Add "num_logbooks" under "helpers.message.general_logbooks".
'general_logbooks#index' to filter with date_from and/or date_to

app/models/general_logbook.rb
- Add scope :date_between.
app/models/general_logbook_filter.rb
- Add attr_reader :date_from and :date_to, and modify the methods
  according to the additions.
app/views/general_logbooks/index.html.erb
- Add text_field for date_from and date_to.
config/locales/ja.yml
- Add "date_from" and "date_to" under "helpers.label.general_logbook_filter".
'general_logbooks#index' to supply pull-down to select logtype

app/helpers/general_logbooks_helper.rb
- Alter displaying_value() to use GeneralLogbooksHelper::TYPE_SELECTION
  to get a return value for argument column_name of 'type'.
app/models/general_logbook_filter.rb
- Add attr_reader :type and modify the methods according to the addition.
app/views/general_logbooks/index.html.erb
- Add select for :type.
config/locales/ja.yml
- Add "type" under "helpers.label.general_logbook_filter".
- Remove "type.*" under "activerecord.attributes.general_logbook".
'general_logbooks#index' to supply pull-down to select priority

app/helpers/general_logbooks_helper.rb
- Alter displaying_value() to use GeneralLogbooksHelper::PRIORITY_SELECTION
  to get a return value for argument column_name of 'priority'.
app/models/general_logbook_filter.rb
- Add attr_reader :priority and modify the methods according to the addition.
app/views/general_logbooks/index.html.erb
- Add select for :priority.
config/locales/ja.yml
- Add "priority" under "helpers.label.general_logbook_filter".
- Remove "priority.*" under "activerecord.attributes.general_logbook".
'general_logbooks#index' to supply pull-down to select status

app/helpers/general_logbooks_helper.rb
- Alter displaying_value() to use GeneralLogbooksHelper::STATUS_SELECTION
  to get a return value for argument column_name of 'status'.
app/models/general_logbook_filter.rb
- Add attr_reader :status and modify the methods according to the addition.
app/views/general_logbooks/index.html.erb
- Add select for :status.
config/locales/ja.yml
- Add "status" under "helpers.label.general_logbook_filter".
- Remove "general_logbook.status.*" under "activerecord.values".
'general_logbooks#index' to show help for text_field input

app/assets/stylesheets/style.css
- Add '#general_logbooks_index_help'.
app/views/general_logbooks/index.html.erb
- Display help for text_field input.
config/locales/ja.yml
- Add "index.help" under "helpers.message.general_logbooks".