Time/EN: Tighten up handling of split times like "five ten"

Summary:
While debugging an attempt to extend our handling of spelled-out
times, I realized that we are being too aggressive in our parsing of
times like "five ten", because we'll parse "five nine" as possibly
meaning "5:09", which isn't something an English speaker would say
(or rather if they did, it's more likely they mean "five (to) six"
or something similar.

Reviewed By: chessai

Differential Revision: D27848429

fbshipit-source-id: 34d783332fd60359ad9b6e7862367453bc93a1d1

CHANGELOG.md

@@ -7,6 +7,7 @@
 ### Rulesets
 * EN (English)
   * Time: Allow latent match for \<part-of-day\> \<latent-time-of-day\>
+  * Time: Avoid parsing phrases like 'two five' as times
 
 * RU (Russian)
   * Duration: Diminutives for minutes and hours

Duckling/Time/EN/Corpus.hs

@@ -112,6 +112,7 @@ negativeCorpus = (testContext, testOptions, examples)
       , "A4 A5"
       , "palm"
       , "Martin Luther King' day"
+      , "two three"
       ]
 
 latentCorpus :: Corpus

Duckling/Time/EN/Rules.hs

@@ -766,7 +766,7 @@ ruleHONumeral = Rule
   { name = "<hour-of-day> <integer>"
   , pattern =
     [ Predicate isAnHourOfDay
-    , Predicate $ isIntegerBetween 1 59
+    , Predicate $ isIntegerBetween 10 59
     ]
   , prod = \tokens -> case tokens of
       (Token Time TimeData{TTime.form = Just (TTime.TimeOfDay (Just hours) is12H)