Improve link preview cards (#1330)

* improve card frame

* add placeholder for empty image

* improve layout, Pleroma compatibility, show author name as description fallback

* reset okhttp logging level

* remove unneeded statement

app/src/main/java/com/keylesspalace/tusky/entity/Card.kt

@@ -16,13 +16,17 @@
 package com.keylesspalace.tusky.entity
 
 import android.os.Parcelable
+import android.text.Spanned
+import com.google.gson.annotations.SerializedName
 import kotlinx.android.parcel.Parcelize
+import kotlinx.android.parcel.WriteWith
 
 @Parcelize
 data class Card(
         val url: String,
-        val title: String,
-        val description: String,
+        val title: @WriteWith<SpannedParceler>() Spanned,
+        val description: @WriteWith<SpannedParceler>() Spanned,
+        @SerializedName("author_name") val authorName: String,
         val image: String,
         val type: String,
         val width: Int,

app/src/main/java/com/keylesspalace/tusky/entity/Status.kt

@@ -130,7 +130,7 @@ data class Status(
 
     data class Application (
         val name: String,
-        val website: String
+        val website: String?
     )
 
     companion object {