Include theme descriptions

Signed-off-by: Michal Čihař <michal@cihar.com>

fallen/theme.json

@@ -1,6 +1,7 @@
 {
     "name": "Fallen",
     "version": "0.6",
+    "description": "Fallen theme for phpMyAdmin",
     "author": "Frans Allen",
     "url": "https://www.fransallen.com/",
     "supports": ["4.7"]

metro/theme.json

@@ -1,6 +1,7 @@
 {
-    "name": "pmahomme",
+    "name": "Metro",
     "version": "2.7",
+    "description": "Windows 8 / Metro Theme for phpMyAdmin",
     "author": "hplhu",
     "url": "https://www.phpmyadmin.net/",
     "supports": ["4.7"]

mhn/theme.json

@@ -1,6 +1,7 @@
 {
     "name": "mhn",
     "version": "1.3",
+    "description": "Flat Theme for phpMyAdmin",
     "author": "Mohan Khadka",
     "url": "http://www.mohankhadka.com.np/",
     "supports": ["4.7"]

pmaterial/theme.json

@@ -1,6 +1,7 @@
 {
     "name": "pmaterial",
     "version": "1.2",
+    "description": "Material Theme for phpMyAdmin",
     "author": "Jees K. Denny",
     "url": "https://www.phpmyadmin.net/",
     "supports": ["4.7"]