[VS Code] Add schemas for common files (microsoft#163)

* [VS Code] Add schemas for common files
- settings.json (paconn settings file)
- apiProperties.json
- apiDefinition.swagger.json

The schema for apiDefinition.swagger.json files is modified from the one found at http://schemastore.org/json/.
It includes many 'x-ms-' vendor extensions.

* [apiDefinition.swagger.schema.json] Copy from http://schemastore.org/json/

Author: joem-msft

.vscode/settings.json

@@ -1,16 +1,53 @@
 {
+  "files.associations": {
+    "*.schema.json": "jsonc"
+  },
+  "editor.insertSpaces": true,
+  "[json]": {
     "editor.insertSpaces": true,
-    "[json]": {
-        "editor.detectIndentation": false,
-        "editor.tabSize": 2,
-        "files.trimTrailingWhitespace": true
+    "editor.detectIndentation": false,
+    "editor.tabSize": 2,
+    "files.trimTrailingWhitespace": true,
+    "editor.quickSuggestions": {
+      "strings": true
     },
-    "json.schemas": [
-        {
-            "fileMatch": [
-                "/apiDefinition.swagger.json"
-            ],
-            "url": "http://json.schemastore.org/swagger-2.0"
-        }
-    ]
+    "editor.suggest.insertMode": "replace"
+  },
+  "[jsonc]": {
+    "editor.insertSpaces": true,
+    "editor.detectIndentation": false,
+    "editor.tabSize": 2,
+    "files.trimTrailingWhitespace": true,
+    "editor.quickSuggestions": {
+      "strings": true
+    },
+    "editor.suggest.insertMode": "replace"
+  },
+  "json.schemas": [
+    {
+      "fileMatch": [
+        "/apiDefinition*.swagger.json"
+      ],
+      "url": "./schemas/apiDefinition.swagger.schema.json"
+    },
+    {
+      "fileMatch": [
+        "/*.swagger.json"
+      ],
+      "url": "http://json.schemastore.org/swagger-2.0"
+    },
+    {
+      "fileMatch": [
+        "/certified-connectors/**/settings.json",
+        "/custom-connectors/**/settings.json"
+      ],
+      "url": "./schemas/paconn-settings.schema.json"
+    },
+    {
+      "fileMatch": [
+        "/apiProperties.json",
+      ],
+      "url": "./schemas/paconn-apiProperties.schema.json"
+    }
+  ]
 }