improved/cleaned debug outputs in in rsgxsnetservice.cc. Performed optimization of transaction system: limited the size of message transactions and allowed a much larger transaction timeout to suppress the transaction cancelling epidemic that caused global bandwidth increase and lack of channel/forum propagation

git-svn-id: http://svn.code.sf.net/p/retroshare/code/trunk@7724 b45a01b8-16f6-495d-af2f-9b41ad6348cc