Add support for remove-datacap-proposal

[neithanmo]

This follows lotus implementation where the blob to be signed is:

blob = CBOR([proposalID(u64), allowance(bigint), client_address]) 
signRemoveDataCap(blob)

zemu_test for datacap is not passing as it requires a new release of ledger-filecoin-js, but PR with required changes for that to work is here

:link: zboto Link

[ftheirs]

ETH path was added here: https://github.com/LedgerHQ/ledger-app-database/pull/35 to solve the failing check

[neithanmo]

close via #129