Add audio control for podcasts

https://github.com/marienfressinaud/FreshRSS/issues/504
Add video control for podcasts

https://github.com/marienfressinaud/FreshRSS/issues/504
SimplePie patch accepted

Merged into master branch of SimplePie
https://github.com/simplepie/simplepie/pull/352
API password user-interface

Removed `noscript` because no JavaScript is needed for the API password.
Added toggle-password
CHANGELOG: podcasts

https://github.com/marienfressinaud/FreshRSS/issues/504
New search system, including date: and pubdate: and combination

Now also accepts combination of #tag and intitle: and inurl: and author:
and the new date: and pubdate:
https://github.com/marienfressinaud/FreshRSS/issues/511
Each search prefix stop at the first space (we should add a possibility
to have quotes for multiple words)
So if you want two words in title, write "intitle:word1 intitle:word2"

Examples of dates:
date:2014
date:2014-02/2014-04 or date:201402/201404
date:P1W for the last week
lib_date comment

https://github.com/marienfressinaud/FreshRSS/issues/511
lib_date comment

https://github.com/marienfressinaud/FreshRSS/issues/511
CHANGELOG searching

https://github.com/marienfressinaud/FreshRSS/issues/511
Search order of filters

For now, process them in the same order as specified by the user
Specifying for instance `date:` first will be much faster than
specifying a free text word first.
https://github.com/marienfressinaud/FreshRSS/issues/511
Add some stick buttons
Update links to change view

- Dropdown menu is transformed into stick buttons
- 3 new icons (view-normal, view-global, view-reader)
- Link to access RSS is now next to these buttons (should we kept it
  here?)
Add icons
Improve page of sharing configuration

- Use sticks
- Change order of buttons
Add titles for help buttons (sharing configuration)
Merge branch 'dev' into 320-template
Improve toggle-password

Add class "active" to button which reveals the password and remove it
when revealing is terminated