Preserve blanks and uses

Return `{ use: "Term" }` and `{ blank: "Blank", value: "Value" }`,
rather than convert those content elements to strings. This will allow
downstream renderers to style term uses and blanks.

Author: kemitchell

README.md

@@ -14,14 +14,14 @@ assert.deepEqual(
   { content: [ 'A' ] })
 ```
 
-Converts term uses to strings:
+Passes term uses through:
 
 ```javascript
 assert.deepEqual(
   resolve(
     { content: [ { use: 'A' } ] },
     { }),
-  { content: [ 'A' ] })
+  { content: [ { use: 'A' } ] })
 ```
 
 Passes definitions through:
@@ -34,14 +34,14 @@ assert.deepEqual(
   { content: [ { definition: 'A' } ] })
 ```
 
-Replaces blanks with provided values, or a blank when none are provided:
+Provides blank values:
 
 ```javascript
 assert.deepEqual(
   resolve(
     { content: [ { blank: 'A' } ] },
     { A: '1' }),
-  { content: [ '1' ] })
+  { content: [ { blank: 'A', value: '1' } ] })
 
 assert.deepEqual(
   resolve(
@@ -102,19 +102,6 @@ assert.deepEqual(
 
 ```
 
-Concatenates strings and contiguous objects that are resolved to strings:
-
-```javascript
-assert.deepEqual(
-  resolve({ content: [ 'A', { use: 'B' } ] }, { }).content,
-  [ 'AB' ])
-
-assert.deepEqual(
-  resolve({ content: [ { use: 'A' }, 'B' ] }, { }).content,
-  [ 'AB' ])
-
-```
-
 Preserves conspicuous formatting flags:
 
 ```javascript

element.js

@@ -7,7 +7,7 @@ module.exports = function(element, values, numbering, headings) {
   if (predicate.text(element)) {
     return element }
   else if (predicate.use(element)) {
-    return element.use }
+    return element }
   else if (predicate.child(element)) {
     element.numbering = numbering.numbering
     element.form = resolve(
@@ -44,9 +44,9 @@ module.exports = function(element, values, numbering, headings) {
     var value = element.blank
     // Filled
     if (values.hasOwnProperty(value)) {
-      return values[value] }
+      return { blank: value, value: values[value] } }
     // Empty
     else {
-      return {blank: value} } }
+      return { blank: value } } }
   else {
     throw new Error('Invalid content: ' + JSON.stringify(element)) } }