Support retrieving of attachments
Show progress indicator even when loading the page

If the feed item contains images, loading the page can take some time.
Therefore, show the progress indicator while the page is loading.
Fix Prev/Next buttons when reading oldest items first

The toolbar buttons for jumping to the next/previous items were
inverted, when ttrss was configured to read oldest articles first.
added note in project.pro for MeeCoLay
Merge pull request #50 from mardy/attachments

Attachments
Merge pull request #51 from mardy/oldest-first

Fix Prev/Next buttons when reading oldest items first
added contributors.md and added mardy
chinese translation thanks to gwmgdemj
update czech translation from transifex
added setting for disabling autologin on start, closes #52
updated translation files
updated english translations
copyright note update
version bump
clean up
cleanup
updated language files
a little code refactoring
some more refactoring
added gwmgdemj to about page