Fix mac, windows, linux builds
Remove deprecated parameter to chain_database_impl::open_database
Improve #409: Add a what() message with human-readable error message

It's still an exception dump, but at least if you look in it, there's a
clear reason why the operation failed.
Close #411: Add debug API with relevant commands

Create a new API category, debug, and migrate the
blockchain_start_simulated_time and blockchain_advance_time calls to it.
Resolve #423

Pretty self-explanatory. A flags enum is now used instead of a pair of
booleans.

The only caveat here is that the function takes an int type, due to a
stupid bug in C++ that says that (enum_val_a | enum_val_b) is of type
int and may not implicitly cast back to type enum.
Partial fix for the problem we're having with peers disconnecting and causing us to fork.  Disconnect peers that are idle for more than two block intervals, and reschedule any item requests that we were expecting them to fulfill
Merge branch 'master' of github.com:BitShares/bitshares_toolkit

Conflicts:
	libraries/client/client.cpp
	libraries/wallet/include/bts/wallet/wallet.hpp
Fix next block production time in get_info