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