fix: make finance book field as link field and rectify fetch_from
diff --git a/erpnext/assets/doctype/asset/asset.json b/erpnext/assets/doctype/asset/asset.json
index 6b3c3cc73..bbe92f6 100644
--- a/erpnext/assets/doctype/asset/asset.json
+++ b/erpnext/assets/doctype/asset/asset.json
@@ -1812,8 +1812,9 @@
    "bold": 0, 
    "collapsible": 0, 
    "columns": 0, 
+   "fetch_from": "company.default_finance_book",
    "fieldname": "default_finance_book", 
-   "fieldtype": "Read Only", 
+   "fieldtype": "Link",
    "hidden": 1, 
    "ignore_user_permissions": 0, 
    "ignore_xss_filter": 0, 
@@ -1824,12 +1825,12 @@
    "label": "Default Finance Book", 
    "length": 0, 
    "no_copy": 0, 
-   "options": "company.default_finance_book", 
+   "options": "Finance Book",
    "permlevel": 0, 
    "precision": "", 
    "print_hide": 0, 
    "print_hide_if_no_value": 0, 
-   "read_only": 0, 
+   "read_only": 1,
    "remember_last_selected_value": 0, 
    "report_hide": 0, 
    "reqd": 0, 
@@ -1882,7 +1883,7 @@
  "issingle": 0, 
  "istable": 0, 
  "max_attachments": 0, 
- "modified": "2019-01-15 16:12:48.314196",
+ "modified": "2019-02-12 11:29:01.747819",
  "modified_by": "Administrator", 
  "module": "Assets", 
  "name": "Asset",