The release notes for 0.15 seem to explain it:
https://bitcoin.org/en/release/v0.15.0.1#multi-wallet-support2nd paragraph explains how to use multiple wallets:
Multi-wallet is enabled by using more than one -wallet argument when starting Bitcoin, either on the command line or in the Bitcoin config file.
Then to access a specific wallet, check the 3rd bullet point down regarding changes to RPC interface:
When running Bitcoin Core with multi-wallet, wallet-level RPC methods must specify the wallet for which theyre intended in every request. HTTP RPC requests should be send to the :/wallet// endpoint, for example: 127.0.0.1:8332/wallet/wallet1.dat/. bitcoin-cli commands should be run with a -rpcwallet option, for example: bitcoin-cli -rpcwallet=wallet1.dat getbalance.
Can I store more than one type of crypto coin on a Bitcoin core wallet? And what types of coins can I store? Or did I misunderstand what you all are talking about?