Add bolt11 test vector with amount in p units

This closes lightning#692.
+
+Breakdown:
+
+* `lnbc`: prefix, Lightning on bitcoin mainnet
+* `9678785340p`: amount (9678785340 pico-bitcoin = 967878534 milli satoshi)
+* `1`: Bech32 separator
+* `pwmna7l`: timestamp (1572468703)
+* `p`: payment hash...
+* `d`: short description
+  * `8d`: `data_length` (`8` = 7, `d` = 13; 7 * 32 + 13 == 237)
+  * `gfkx7cmtwd68yetpd5s9xar0wfjn5gpc8qhrsdfq24f5ggrxdaezqsnvda3kkum5wfjkzmfqf3jkgem9wgsyuctwdus9xgrcyqcjcgpzgfskx6eqf9hzqnteypzxz7fzypfhg6trddjhygrcyqezcgpzfysywmm5ypxxjemgw3hxjmn8yptk7untd9hxwg3q2d6xjcmtv4ezq7pqxgsxzmnyyqcjqmt0wfjjq6t5v4khx`: 'Blockstream Store: 88.85 USD for Blockstream Ledger Nano S x 1, \"Back In My Day\" Sticker x 2, \"I Got Lightning Working\" Sticker x 2 and 1 more items'
+* `x`: expiry time
+  * `qy`: `data_length` (`q` = 0, `y` = 2; 0 * 32 + 4 == 4)
+  * `jw5q`: 604800 seconds (`j` = 18, `w` = 14, `5` = 20, `q` = 0; 18 * 32^3 + 14 * 32^2 + 20 * 32 + 0 == 604800)
+* `r`: tagged field: route information
+  * `zj`: `data_length` (`z` = 2, `j` = 18; 2 * 32 + 18 == 82)
+* `s4x9qlmd57lq7wwr23n3a6pkayy3jpfucyptlncs2maswe3dnnjy3ce2cgrvykmxlfpvn6ptqfqz4df5uaulvd4hjkckuqxrqqkz8jgp`: signature
+* `hputwh`: Bech32 checksum
+
 > ### Please send $30 for coffee beans to the same peer, which supports features 1 and 9
 > lnbc25m1pvjluezpp5qqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqypqdq5vdhkven9v5sxyetpdees9qzsze992adudgku8p05pstl6zh7av6rx2f297pv89gu5q93a0hf3g7lynl3xq56t23dpvah6u7y9qey9lccrdml3gaqwc6nxsl5ktzm464sq73t7cl

11-payment-encoding.md

@@ -534,6 +534,27 @@ Breakdown:
   * `6c6e626332306d0b25fe64570d0e496dbd9f8b0d000dbb44824f751380da37c6dba89b14f6f92047d63f576e304021a00008101820283038404800081018202830384048000810182028303840480810243500c318a1e0a628b34025e8c9019ab6d09b64c2b3c66a693d0dc63194b02481931000` hex of data for signing (prefix + data after separator up to the start of the signature)
   * `399a8b167029fda8564fd2e99912236b0b8017e7d17e416ae17307812c92cf42` hex of SHA256 of the preimage
 
+> ### Please send 0.00967878534 BTC for a list of items within one week, amount in pico-BTC
+> 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
+
+Breakdown:
+
+* `lnbc`: prefix, Lightning on bitcoin mainnet
+* `9678785340p`: amount (9678785340 pico-bitcoin = 967878534 milli satoshi)
+* `1`: Bech32 separator
+* `pwmna7l`: timestamp (1572468703)
+* `p`: payment hash...
+* `d`: short description
+  * `8d`: `data_length` (`8` = 7, `d` = 13; 7 * 32 + 13 == 237)
+  * `gfkx7cmtwd68yetpd5s9xar0wfjn5gpc8qhrsdfq24f5ggrxdaezqsnvda3kkum5wfjkzmfqf3jkgem9wgsyuctwdus9xgrcyqcjcgpzgfskx6eqf9hzqnteypzxz7fzypfhg6trddjhygrcyqezcgpzfysywmm5ypxxjemgw3hxjmn8yptk7untd9hxwg3q2d6xjcmtv4ezq7pqxgsxzmnyyqcjqmt0wfjjq6t5v4khx`: 'Blockstream Store: 88.85 USD for Blockstream Ledger Nano S x 1, \"Back In My Day\" Sticker x 2, \"I Got Lightning Working\" Sticker x 2 and 1 more items'
+* `x`: expiry time
+  * `qy`: `data_length` (`q` = 0, `y` = 2; 0 * 32 + 4 == 4)
+  * `jw5q`: 604800 seconds (`j` = 18, `w` = 14, `5` = 20, `q` = 0; 18 * 32^3 + 14 * 32^2 + 20 * 32 + 0 == 604800)
+* `r`: tagged field: route information
+  * `zj`: `data_length` (`z` = 2, `j` = 18; 2 * 32 + 18 == 82)
+* `s4x9qlmd57lq7wwr23n3a6pkayy3jpfucyptlncs2maswe3dnnjy3ce2cgrvykmxlfpvn6ptqfqz4df5uaulvd4hjkckuqxrqqkz8jgp`: signature
+* `hputwh`: Bech32 checksum
+
 > ### Please send $30 for coffee beans to the same peer, which supports features 1 and 9
 > lnbc25m1pvjluezpp5qqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqypqdq5vdhkven9v5sxyetpdees9qzsze992adudgku8p05pstl6zh7av6rx2f297pv89gu5q93a0hf3g7lynl3xq56t23dpvah6u7y9qey9lccrdml3gaqwc6nxsl5ktzm464sq73t7cl