chore(bitswap) remove dead/unused wantlist code
refac(bitswap) privatize send block
feat(bitswap:strategy) add interfaces

refac(bitswap:strategy) update interface
refac(bitswap) inline helper methods

for readability
chore(bitswap) rm vestigial fields
chore(bitswap) rm halt chan since bitswap has no daemon
style(bitswap) sort in c'tor
refac(bit swap) move ledger to strategy package
fix(bitswap:strategy) move key set
feat(bit swap) stub out a concrete strategist
Merge branch 'feat/bitswap-strategy-2014-09-17' into net