fix(blog): Fix article image in front matter

docs/content/blog/2019-02-11-introducing-vendure/index.md

@@ -4,7 +4,7 @@ date: 2019-02-11T10:27:46+01:00
 draft: false
 author: "Michael Bromley"
 images: 
-    - "./introducing-vendure.jpg"
+    - "/blog/2019/02/introducing-vendure/introducing-vendure.jpg"
 aliases:
     - /blog/introducing-vendure/
 ---

docs/content/blog/2019-05-27-beta-release-and-roadmap-2019/index.md

@@ -4,7 +4,7 @@ date: 2019-05-27T10:27:46+01:00
 draft: false
 author: "Michael Bromley"
 images: 
-    - "./blog/introducing-vendure/introducing-vendure.jpg"
+    - "/blog/2019/02/introducing-vendure/introducing-vendure.jpg"
 aliases:
     - /blog/beta-release-and-roadmap-2019/
 --- 

docs/content/blog/2019-08-28-summer-update/index.md

@@ -4,7 +4,7 @@ date: 2019-08-28T10:00:46+01:00
 draft: false
 author: "Michael Bromley"
 images: 
-    - "./falkert-austria-michael-bromley.jpg"
+    - "/blog/2019/08/vendure-summer-update-towards-v1.0/falkert-austria-michael-bromley.jpg"
 ---
 
 After pausing for a refreshing week high in the Austrian Alps, development of Vendure continues apace. This blog post explains an upcoming change to the version numbering prior to 1.0, as well as a discussion of the remaining work to be done for the first stable release.