Update test

- Change hugo export dir to a relative path
- Tests for property drawer parsing during subtree exports (does not
  work at the moment)

tests/org/small1/small1.org

@@ -1,9 +1,18 @@
 #+TITLE: My Blog
-#+HUGO_EXPORT_DIR: ~/temp/small1/
+#+HUGO_EXPORT_DIR: ../../md/
 #+HUGO_SECTION: posts
 
 # 1. Load `ox-hugo'
 # 2. M-x org-hugo-walk-headlines
 
 * Post 1
+:PROPERTIES:
+:DATE:     June 11, 2000
+:END:
 Something
+* Post 2
+:PROPERTIES:
+:CUSTOM_ID: testxyz
+:FOO: There
+:END:
+Something Else