new splash screen

why:

- the current splash-screen has no referring to official images on - https://en.bitcoin.it/wiki/Promotional_graphics
- the current splash screen only exists in a low res jpg
- current splash screen looks dark and "hackish"
- new splash screen should generate positive, "trust-emotions".
- new splash screen gives the user infos about the running client.
- new splash screen can handle long messages (in a lot of - languages the text is cropped in current release)

- new size (x2) 400x312

- contains textual information about the client
- textinfos are dynamicly written to the pixmap

when -testnet is switch on, the splashscreen will show the bitcoin logo in testnet-color (as well as a text [testnet])

example: https://dl.dropbox.com/u/7383846/new_bitcoin_splash.png

bitcoin-qt.pro

@@ -210,7 +210,8 @@ HEADERS += src/qt/bitcoingui.h \
     src/txdb.h \
     src/leveldb.h \
     src/threadsafety.h \
-    src/limitedmap.h
+    src/limitedmap.h \
+    src/qt/splashscreen.h
 
 SOURCES += src/qt/bitcoin.cpp \
     src/qt/bitcoingui.cpp \
@@ -277,7 +278,8 @@ SOURCES += src/qt/bitcoin.cpp \
     src/qt/rpcconsole.cpp \
     src/noui.cpp \
     src/leveldb.cpp \
-    src/txdb.cpp
+    src/txdb.cpp \
+    src/qt/splashscreen.cpp
 
 RESOURCES += src/qt/bitcoin.qrc