Prune provably-unspendable outputs
Squashed 'src/leveldb/' changes from be1b0ff..936b461

936b461 Merge upstream LevelDB 1.13.
748539c LevelDB 1.13

git-subtree-dir: src/leveldb
git-subtree-split: 936b4613ea4551992e6096b1e05eeefc09a20e3b
Merge src/leveldb changes for LevelDB 1.13
Set Accept: application/bitcoin-paymentrequest header

Suggestion from BitPay: set an Accept: HTTP header when
fetching payment requests / payment ACKs.
[wallet] Consider generated coins mature at COINBASE_MATURITY+1

We're not seeing large reorgs that would justify waiting a large
 amount past the rule required maturity, and the extra three
 hours is just a nuisance. Take one more block to at least give
 the 100th block time to propagate.
RPC: add getrawchangeaddress, for raw transaction change destinations
[raw] reject insanely high fees by default in sendrawtransaction

There have been several incidents where mainnet experimentation with
 raw transactions  resulted in insane fees.  This is hard to prevent
 in the raw transaction api because the inputs may not be known.
 Since sending doesn't work if the inputs aren't known, we can catch
 it there.

This rejects fees > than 10000 * nMinRelayTxFee or 1 BTC with the
 defaults and can be overridden with a bool at the rpc.
improve wallet load time by removing duplicated calls to EC_KEY_check_key and adding a hash for vchPubKey/vchPrivKey entries in wallet.dat

backwards compatible with previous wallet.dat format
verify vchPubKey matches calculated public key unless fSkipCheck is set
qt: Handle address purpose in incremental updates

Correctly use the purpose of addresses that are added after the start
of the client. Addresses with purpose "refund" and "change" should not
be visible in the GUI. This is now handled correctly.
qt: Display txfee in first sendCoinsDialog message box

Signed-off-by: Jonas Schnelli <jonas.schnelli@include7.ch>
Bitcoin-Qt: allow to differentiate Qt log entries from core

- prepend "Bitcoin-Qt" in front of debug.log entries, which come from Qt
- move DebugMessageHandler installation upwards to the event handler
  installation, which fits much better
Merge pull request #2963 from Diapolo/log-qt

Bitcoin-Qt: allow to differentiate Qt log entries from core
Merge pull request #2951 from laanwj/2013_08_addressbook_purpose

[Qt] Handle address purpose in incremental updates
Fix typo in a comment: it's base58, not base48.
Merge pull request #2967 from tstranex/master

Fix typo in a comment: it's base58, not base48.
Merge pull request #2958 from laanwj/2013_08_txfee2

[Qt] Display txfee in first sendCoinsDialog message box
Merge pull request #2948 from jgarzik/changeaddr

RPC: add getrawchangeaddress, for raw transaction change destinations
Don't warn about forks while fIsInitialDownload
Merge pull request #2944 from gavinandresen/acceptheader

Set Accept: application/bitcoin-paymentrequest header