ProfilePage: Move the spinner into a stack

... so we don't move widgets around when showing/hiding it.
ProfilePage: Don't show the progress spinner...

... if we already have data of that user in the database.
TweetInfoPage: Fetch information for correct tweet

If the shown tweet is actually a retweet, we need to fetch the
information of the source tweet.

See #205
inline media: Hide if max-size is too small

If the max-media-size is below 0.001, we can just assume that no media
will be loaded at all and we can just hide it altogether.
Utils: Improve error messages

Print the line + file where the message/error object occurred in order
to better identify exceptions like the one from #210.
Fix the build with -Werror=format-security
Fix man page installation directory

Use the right automake invocation to make the man page properly go to
/usr/share/man/man1.
Merge pull request #213 from kalev/format-security

Fix the build with -Werror=format-security
Merge pull request #214 from kalev/man-directory

Fix man page installation directory
profile-page: Fix follow/more-button height
refine message list spacing

It was a bit too tight before - more padding makes it easier to
read and feels lighter.
use adwaita icon theme
add a border to the sidebar

This makes the sidebar more distinct.
sql: Show column values on sql errors
list-statuses-page: Use symbolic refresh icon
TweetListEntry: Remove custom draw implementation
account-list-entry: Remove xpad + label

xpad is deprecated and we never used the label anyway
Correct the appdata file name

It has to match the desktop file name.
Merge pull request #216 from kalev/appdata-file-name

Correct the appdata file name
css: Give each tweet a border-bottom