More helpful headline for map saving error popup
Commit from Unknown Horizons Translation Server by user Chris Oelmueller.: 209 of 369 strings translated (14 fuzzy).
Replace dummy of message_widget with real instance.

This is done because message_widget was needed to show messages in the editor. A logbook dummy is created in order for message_widget to work.
Implement quicksave and autosave for editor; fix #1935
Modify save_map to return whether it was succesful
Clean up error popup on failed quicksave

Drop unicode in gettext-wrapped strings, use format()
Modify editor quicksave and autosave to handle failure
Merge pull request #2033 from ThePawnBreak/editor-mapsave

Editor mapsave #1935
Add showprice keyword arg to ImageStatusFillButton init
Add information about price in tooltip in Select Resources widget
Add support for different buy and sell prices; show price as float
Merge pull request #2034 from ThePawnBreak/showprice

Add price tooltip to Select Resources tab. Fixes #1637
Whitespace
Add ThePawnBreak to list of contributors
Drop a few assumptions about amount of music tracks

In particular we would crash if there were three or fewer tracks
available as a whole and if the menu music tried to refresh playlist
while no menu_music existed at that point.
Now restricts the deque length such that it can hold at most one track
less than the amount of tracks available.
Merge pull request #2035 from ThePawnBreak/authors

Add ThePawnBreak to list of contributors
Add Peer Gynt Suite No. 1, Op. 46 - I. Morning

composed by Edvard Grieg, performed by the Czech National Symphony Orchestra
licensed as public domain. More details can be found at http://www.musopen.org/music/piece/1568
credits: Remove support for wide pages, wrap longer lines

It destroyed the layout pretty much and didn't go well with adding new
sections to the right page of the only section using it (Special Thanks).
Still not convinced this is the optimal solution, but why not use the
space if we have it.
Add portfolio website section for artists

Intended for use with audio and graphics artists who can add a link to
our in-game credits this way. The "Special Thanks" section was chosen
because it contains links to other pages already.
Grammar fix