Removing undocumented alias (#189)

`type: string` is an undocumented alias for `type: text`. It's quite confusing because it's used in these table examples where it's 2 lines below `text`. This example has been around since @mberg's initial commit of `xlsform.md` - 76b3d25 pyxform compiles the two types the same
XLSForm · May 19, 2020 · 0ae9c71 · 0ae9c71
1 parent 3f96358
commit 0ae9c71
Showing 1 changed file with 2 additions and 2 deletions.
diff --git a/_sections/home-english.md b/_sections/home-english.md
@@ -948,7 +948,7 @@ In your **survey** tab, group together the questions you would like to appear on
 | begin group | group1   |                      | field-list |
 | text        | name     | Respondent's name    |            |
 | integer     | age      | Respondent's age     |            |
-| string      | address  | Respondent's address |            |
+| text        | address  | Respondent's address |            |
 | end group   |          |                      |            |
 | =========   | ======== | ======               | ====       |
 | survey      |          |                      |            |
@@ -976,7 +976,7 @@ In your **survey** tab, group together the questions you would like to appear in
 | begin group | group1   |                      |            |
 | text        | name     | Respondent's name    | w3         |
 | integer     | age      | Respondent's age     | w1         |
-| string      | address  | Respondent's address | w4         |
+| text        | address  | Respondent's address | w4         |
 | end group   |          |                      |            |
 | =========   | ======== | ======               | ====       |
 | survey      |          |                      |            |