getBundlesFromAddresses deprecation

[Cylix]

From #304 (iota.lib.js changes):

getBundlesFromAddresses() is deprecated and will probably be removed in next major version.
Reason for deprecating is poor performance; number of bundle instances can be any, and fetching all bundles lazily is preferred for most use cases. I think that findTransactions() on addresses is fine for most cases.

getTransfers() is deprecated
calls getBundlesFromAddresses

transfers field of getAccountData() is deprecated
Reason for this is internal getBundlesFromAddresses call to fetch full bundles. transactions field was added as replacement which contains transactions (instead of bundles) as returned by findTransactions() on account addresses. (https://github.com/iotaledger/iota.lib.js/blob/next/packages/core/src/createGetAccountData.ts#L154)

Everything is kind of related here and change sounds reasonable for the performance issues. We already tried to have some improvements for getBundlesFromAddresses, but there is not so much room for improvement as most of the performance is bound by IRI execution time.