Merge pull request #72 from vikramrajkumar/btsx

Merge upstream
adding expiration to short positions
Update submodules
adding expiration to output of shorts
Merge branch 'develop' of github.com:BitShares/bitshares_toolkit into develop
reduce short expiration time to 2 hours for test network
Update submodules
dry run 19
Fix bug in transaction_builder

Sometimes the builder generated a bad transaction that overwithdrew from
a balance. This is now fixed.
Fix bug in transaction_builder

Sometimes the builder generated a bad transaction that overwithdrew from
a balance. This is now fixed.
More progress on transaction scanning rewrite
Merge branch 'develop' of github.com:BitShares/bitshares_toolkit into develop
Merge branch 'dryrun-19' into develop
Update submodules
Merge branch 'develop' into btsx

Conflicts:
	libraries/blockchain/CMakeLists.txt
	programs/qt_wallet
	programs/web_wallet
Update submodules
Set next hardfork block number
Restore BTS_BLOCKCHAIN_MAX_SHORT_PERIOD_SEC
Old shorts expire after 1 year