Fix a typo bug
Correct French translation
Simplify and fix custom filtering

Move most of the custom filtering of participants to a private method.  Fix filtering of participants for download.  (Before, custom filter was not applied for download.)
Fix a custom filter input field label attribute
Use scopes instead of arrays in index views
Simplify participant filtering form action URL
Change org utility tabs, add speaker email lists
Separate 'page_count' paginating parameter

Separate 'page_count' from other paginating parameters because it plays a different role: it is not used as a request parameter.
Use default nil 'action_url' in paginating_form
Format
Small change in hard line breaks on Program page
Add 'show_as' view parameter

Rename and modify the method for extracting pagination parameters to include 'show_as' string parameter.
Simplify hidden parameters in participant index

Simplify the code specifying hidden parameters in participant index.
Work on CSS and pagination button styles
Buttons to select table/email list presentation

Add helper function to generate buttons to select between different presentation of the index view, for example between table and email list presentations.
Allow to chose between table and email_list

Allow to chose the form of participant index between a table and an email_list.
Add custom filter for speakers
Add translation for a non-existent attribute name

(just in case).
Comment out unnecessary utility tab actions

Comment out the actions for utility tabs listing speaker email addresses.
Allow to filter talks by type and list abstracts