add License activity (#689)

* convert AboutActivity to Kotlin, use BottomSheetActivity for account resolving

* improve AboutActivity

* new License activity

* fix filemojicompat url

app/src/main/java/com/keylesspalace/tusky/view/LicenseCard.kt

@@ -0,0 +1,61 @@
+/* Copyright 2018 Conny Duck
+ *
+ * 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.view
+
+import android.content.Context
+import android.support.v7.widget.CardView
+import android.util.AttributeSet
+import com.keylesspalace.tusky.R
+import com.keylesspalace.tusky.util.LinkHelper
+import com.keylesspalace.tusky.util.ThemeUtils
+import com.keylesspalace.tusky.util.hide
+import kotlinx.android.synthetic.main.card_license.view.*
+
+
+class LicenseCard
+@JvmOverloads constructor(
+        context: Context,
+        attrs: AttributeSet? = null,
+        defStyleAttr: Int = 0
+) : CardView(context, attrs, defStyleAttr) {
+
+
+    init {
+        inflate(context, R.layout.card_license, this)
+
+        setCardBackgroundColor(ThemeUtils.getColor(context, android.R.attr.colorBackground))
+
+        val a = context.theme.obtainStyledAttributes(attrs, R.styleable.LicenseCard, 0, 0)
+
+        val name: String? = a.getString(R.styleable.LicenseCard_name)
+        val license: String? = a.getString(R.styleable.LicenseCard_license)
+        val link: String? = a.getString(R.styleable.LicenseCard_link)
+        a.recycle()
+
+        licenseCardName.text = name
+        licenseCardLicense.text = license
+        if(link.isNullOrBlank()) {
+            licenseCardLink.hide()
+        } else {
+            licenseCardLink.text = link
+            setOnClickListener { LinkHelper.openLink(link, context) }
+        }
+
+    }
+
+
+}
+