Share filters with web client (#956)

* First step toward synchronized content filters

* Add simple filter management UI

* Remove old regex filter UI

* More cleanup

* Escape filter phrases when applying them via regex

* Apply code review feedback

* Fix live timeline update when filters change

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

@@ -0,0 +1,47 @@
+/* Copyright 2018 Levi Bard
+ *
+ * This file is a part of Tusky.
+ *
+ * This program is free software; you can redistribute it and/or modify it under the terms of the
+ * GNU General Public License as published by the Free Software Foundation; either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * Tusky is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
+ * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
+ * Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with Tusky; if not,
+ * see <http://www.gnu.org/licenses>. */
+
+package com.keylesspalace.tusky.entity
+
+import com.google.gson.annotations.SerializedName
+
+data class Filter (
+    val id: String,
+    val phrase: String,
+    val context: List<String>,
+    @SerializedName("expires_at") val expiresAt: String?,
+    val irreversible: Boolean,
+    @SerializedName("whole_word") val wholeWord: Boolean
+) {
+    public companion object {
+        const val HOME = "home"
+        const val NOTIFICATIONS = "notifications"
+        const val PUBLIC = "public"
+        const val THREAD = "thread"
+    }
+
+    override fun hashCode(): Int {
+        return id.hashCode()
+    }
+
+    override fun equals(other: Any?): Boolean {
+        if (other !is Filter) {
+            return false
+        }
+        val filter = other as Filter?
+        return filter?.id.equals(id)
+    }
+}
+