qt: don't show rpcconnect command line option in help

GUI can't connect to RPC. Showing this option in the help confuses
people, so remove it.
Add test patches for pull-tester to contrib/
Merge pull request #2514 from TheBlueMatt/master

Add test patches for pull-tester to contrib/
Use a uint256 for bnChainWork

Every block index entry currently requires a separately-allocated
CBigNum. By replacing them with uint256, it's just 32 bytes extra
in CBlockIndex itself.

This should save us a few megabytes in RAM, and less allocation
overhead.
Merge pull request #2513 from laanwj/2013_04_gui_remove_rpcconnect

qt: don't show rpcconnect command line option in help
Merge pull request #2418 from sipa/uintwork

Use a uint256 for bnChainWork