tests: bitswap ledger tests modified
tests: bitswap ledger tests modified

Updated the `TestBitswapLedger*` tests and added assertions to check concrete
values for ledgers (rather than just checking that two peers' ledgers match).
The names for these tests were also changed from the previous commit, according
to 's/BytesSent/Ledger/'.

License: MIT
Signed-off-by: David Grisham <002ac86fccf59f1b61993ff1f9bbef83457c10ec@mines.edu>

Luzifer/go-ipfs,ianopolous/go-ipfs,ianopolous/go-ipfs,chriscool/go-ipfs,MichaelMure/go-ipfs,Luzifer/go-ipfs,Quantomicus/go-ipfs,JustinDrake/go-ipfs,kyledrake/go-ipfs,JustinDrake/go-ipfs,chriscool/go-ipfs,Quantomicus/go-ipfs,ianopolous/go-ipfs,OpenBazaar/go-ipfs,MichaelMure/go-ipfs,JustinDrake/go-ipfs,kyledrake/go-ipfs,WilliButz/go-ipfs,MichaelMure/go-ipfs,OpenBazaar/go-ipfs,Quantomicus/go-ipfs,Luzifer/go-ipfs,WilliButz/go-ipfs,OpenBazaar/go-ipfs,WilliButz/go-ipfs,kyledrake/go-ipfs,chriscool/go-ipfs