added SetBitcoinAddress and GetBitcoinAddress methods on CScript,
critsect interlocks around mapAddressBook,
added some random delays in tx broadcast to improve privacy,
now compiles with MSVC 8.0
git-svn-id: https://bitcoin.svn.sourceforge.net/svnroot/bitcoin/trunk@60 1a98c847-1fd6-4fd8-948a-caf3550aa51b