Add download status to statusbar

It overlaps the first status field but is only visible while downloading
and shortly after.

Active downoads are indicated by yellow background, a text and a
progress bar.

If all downloads finish, the bar turns greend and disappers after 5 sec.

The data is collected from DownloadObserver and uses a wxTimer to get
updates.

see  Issue #49
Merge pull request #75 from baracoder/taskbar

Add download status to statusbar
unused code
fix #77
possible fix for #72
try to fix autoscroll on win7  #72

http://wiki.wxwidgets.org/WxTextCtrl#Scrolling
"ScrollLines will ensure the scroll bar is at the real end of the range, not further."
ring_sound.h: split very long line
gitignore: ignore generated doxygen html files
Merge pull request #78 from baracoder/fix_74

Fix 74
remove report statistics:
- can be already collected indirectly at lobby server
- updates are already checked differently
Merge branch 'master' of github.com:springlobby/springlobby
remove introguide / link to online version / cleanup
make cache path of springlobby independant of unitsync / spring:
- this allow (re) use of cached images & stuff
- logs are written in one dir and not across all spring installations
- no need for unitsync to be loaded in most cases
lang!
remove unused torrent settings
fix chatlog path
reenable connection timeout to server
remove ChangeLog, use git log instead!
remove obsolete NEWS file
add git pre-commit hook for coding style