Slightly tweak error when unable to bind port

A slight improvement over 2d2d8fae3d8bc4e82dc631d93c6e19f954bbee04 -- we don't know that it's the daemon, it could be the GUI.
Update the list of threads to the current state.
Make mining fee policy match relay fee policy.

This resolves a case in which a mismatch could be used to bloat up the
mempool by sending transactions that pay enough fee to relay, but not
to be mined, with the default policies.
Add script test to prove that OP_0 evaluates as the empty vector, rather than [0].
qt: Make it possible again to specify -testnet in config file

Changes for the datadir chooser have made it impossible to specify
the network (testnet/regtest) in the configuration file for the GUI.

Reorganize the initialization sequence to make this possible again.

- Moves the "datadir" QSetting so that is no longer dependent on the
  network-specific application name (doing otherwise would create a
  chicken-and-egg problem).

- Re-initialize translations after choosing network. There may be a
  different language configured in network-specific settings
  (slim chance, but handle it for sanity).

Fixes point 1 of #3840.
Merge branch 'match_relay_fee' of git://github.com/mikehearn/bitcoin
Merge pull request #3844

c52c4e5 qt: Make it possible again to specify -testnet in config file (Wladimir J. van der Laan)
minor style cleanups
Fix missing wallet lock in CWallet::SyncTransaction(..)
Merge pull request #3808 from paveljanik/master

DOC: Update the list of threads to the current state.
[Qt] Fill in label from address book also for URIs
Merge pull request #3841 from schildbach/script-tests-OP_0

Add script test to prove that OP_0 evaluates as the empty vector.
Adjust branding in datadir lock error message
Merge pull request #3846

3f2a017 [Qt] Fix coin control qt5 checkbox bug in tree mode (Cozz Lovan)
Merge pull request #3849 from cozz/cozz2

Fix missing wallet lock in CWallet::SyncTransaction(..)
Add a "relayfee" field to getinfo.

This shows the minimum relay fee for non-free transactions in btc/kb.

The armory developers requested this so that they can prevent users from
 creating transactions that not even their local bitcoind will relay.

This also slightly reorders the getinfo output so that the fee related
 lines are grouped and changes the help text to reflect that the units
 are btc/kb.
qt: Show also value for options overridden on command line

Currently only the name of the option is shown for GUI options
overridden by command line (or configuration file). This commit
adds the value of the options as well, which is useful for
troubleshooting.
Update docs about boost on unix
[Qt] Dont set table color in coin control
Merge pull request #3868 from gmaxwell/minfeeinfo

Add a "relayfee" field to getinfo.