feat(libpostal_patch): enable field mapping for "unit"

controller/libpostal.js

@@ -17,7 +17,8 @@ var field_mapping = {
   state_district: 'county',
   state:          'state',
   postcode:       'postalcode',
-  country:        'country'
+  country:        'country',
+  unit:           'unit',
 };
 
 // This controller calls the hosted libpostal service and converts the response

test/unit/controller/libpostal.js

@@ -439,7 +439,7 @@ module.exports.tests.bug_fixes = (test, common) => {
           text: 'original query',
           parser: 'libpostal',
           parsed_text: {
-            // unit: '11',
+            unit: '11',
             number: '1015',
             street: 'nudgee road',
             neighbourhood: 'banyo',
@@ -503,7 +503,7 @@ module.exports.tests.bug_fixes = (test, common) => {
           text: 'original query',
           parser: 'libpostal',
           parsed_text: {
-            // unit: '999',
+            unit: '99',
             number: '11/1015',
             street: 'nudgee road',
             neighbourhood: 'banyo',