Issue #96: Beginning work on a RPC client mode

At this point, the client can take a --client flag which will make
it pass all commands to an RPC server over the network rather than
processing them locally. Unfortunately, the client still starts all
of the normal network node services, so it connects to the network
and downloads the blockchain, etc. when all it should be doing is
connecting to the RPC server.
adding missing file
implementing basic blockchain support for data feeds
resolve conflicts
register update feed op with operation factory
updating webwallet
fix error reporting on wallet name
fix conflict
Merge branch 'develop' of github.com:BitShares/bitshares_toolkit into develop
Merge branch 'develop' of github.com:BitShares/bitshares_toolkit into develop
implementing price change limits based on the 24 hour moving average
merge from develop
implement data feed validation
updates toward publishing price feeds
Merge branch 'develop' of github.com:BitShares/bitshares_toolkit into develop

Conflicts:
	programs/web_wallet
price feeds are now implemented
only keep a short undo history
adding market fees to asset record
Add new RPC call, wallet_account_update_active_key and regression test

Add a new call to update the active key and write a test to verify that
it completes successfully and can be imported into a new wallet. More
testing is necessary.
Fix is_unique_account wrt updated active key

Previously a wallet account was considered different from its blockchain
counterpart if the active key had been updated. This is no longer the
case.