Add knex as dependency for needing packages.

Allows these types to still require knex now that it self bundles its types.

types/bookshelf/package.json

@@ -0,0 +1,6 @@
+{
+    "private": true,
+    "dependencies": {
+        "knex": "^0.16.1"
+    }
+}

types/knex-postgis/package.json

@@ -0,0 +1,6 @@
+{
+    "private": true,
+    "dependencies": {
+        "knex": "^0.16.1"
+    }
+}

types/mock-knex/package.json

@@ -0,0 +1,6 @@
+{
+    "private": true,
+    "dependencies": {
+        "knex": "^0.16.1"
+    }
+}

types/schwifty/package.json

@@ -1,6 +1,7 @@
 {
     "private": true,
     "dependencies": {
+        "knex": "^0.16.1",
         "objection": "^1.1.9"
     }
 }