Modify optparse description format for wallet-tool.

Before this commit, the help message for wallet-tool was
very hard to read; this improves the format of the message
by overriding optparse's default handling of description
paragraphs, making it pass through the string exactly as is,
and also reformatting the string itself.

jmclient/jmclient/wallet_utils.py

@@ -5,7 +5,7 @@ import sqlite3
 import binascii
 from datetime import datetime
 from calendar import timegm
-from optparse import OptionParser
+from optparse import OptionParser, IndentedHelpFormatter
 from numbers import Integral
 from collections import Counter
 from itertools import islice
@@ -29,29 +29,36 @@ DEFAULT_MIXDEPTH = 4
 
 
 def get_wallettool_parser():
-    description = (
-        'Use this script to monitor and manage your Joinmarket wallet.\n'
-        'The method is one of the following: \n'
-        '(display) Shows addresses and balances.\n'
-        '(displayall) Shows ALL addresses and balances.\n'
-        '(summary) Shows a summary of mixing depth balances.\n'
-        '(generate) Generates a new wallet.\n'
-        '(changepass) Changes the encryption passphrase of the wallet.\n'
-        '(history) Show all historical transaction details. Requires Bitcoin Core.'
-        '(recover) Recovers a wallet from the 12 word recovery seed.\n'
-        '(showutxos) Shows all utxos in the wallet.\n'
-        '(showseed) Shows the wallet recovery seed and hex seed.\n'
-        '(importprivkey) Adds privkeys to this wallet, privkeys are spaces or commas separated.\n'
-        '(dumpprivkey) Export a single private key, specify an hd wallet path\n'
-        '(signmessage) Sign a message with the private key from an address in \n'
-        'the wallet. Use with -H and specify an HD wallet path for the address.\n'
-        '(freeze) Freeze or un-freeze a specific utxo. Specify mixdepth with -m.\n'
-        '(gettimelockaddress) Obtain a timelocked address. Argument is locktime value as yyyy-mm. For example `2021-03`\n'
-        '(addtxoutproof) Add a tx out proof as metadata to a burner transaction. Specify path with '
-            '-H and proof which is output of Bitcoin Core\'s RPC call gettxoutproof\n'
-        '(createwatchonly) Create a watch-only fidelity bond wallet')
+
+    # optparse munges description paragraphs. Here we
+    # have a big, complex paragraph which we need to control:
+    class IndentedHelpFormatterWithNL(IndentedHelpFormatter):
+        def format_description(self, description):
+            return description
+
+    description ="""Use this script to monitor and manage your Joinmarket wallet.
+The method is one of the following:
+(display) Shows addresses and balances.
+(displayall) Shows ALL addresses and balances.
+(summary) Shows a summary of mixing depth balances.
+(generate) Generates a new wallet.
+(changepass) Changes the encryption passphrase of the wallet.
+(history) Show all historical transaction details. Requires Bitcoin Core.
+(recover) Recovers a wallet from the 12 word recovery seed.
+(showutxos) Shows all utxos in the wallet.
+(showseed) Shows the wallet recovery seed and hex seed.
+(importprivkey) Adds privkeys to this wallet, privkeys are spaces or commas separated.
+(dumpprivkey) Export a single private key, specify an hd wallet path.
+(signmessage) Sign a message with the private key from an address in
+    the wallet. Use with -H and specify an HD wallet path for the address.
+(freeze) Freeze or un-freeze a specific utxo. Specify mixdepth with -m.
+(gettimelockaddress) Obtain a timelocked address. Argument is locktime value as yyyy-mm. For example `2021-03`.
+(addtxoutproof) Add a tx out proof as metadata to a burner transaction. Specify path with
+    -H and proof which is output of Bitcoin Core\'s RPC call gettxoutproof.
+(createwatchonly) Create a watch-only fidelity bond wallet.
+"""
     parser = OptionParser(usage='usage: %prog [options] [wallet file] [method] [args..]',
-                          description=description)
+                          description=description, formatter=IndentedHelpFormatterWithNL())
     add_base_options(parser)
     parser.add_option('-p',
                       '--privkey',