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/LicenseActivity.kt

@@ -0,0 +1,84 @@
+/* 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
+
+import android.os.Bundle
+import android.support.annotation.RawRes
+import android.util.Log
+import android.view.MenuItem
+import android.widget.TextView
+import com.keylesspalace.tusky.util.IOUtils
+import kotlinx.android.extensions.CacheImplementation
+import kotlinx.android.extensions.ContainerOptions
+import kotlinx.android.synthetic.main.activity_license.*
+import kotlinx.android.synthetic.main.toolbar_basic.*
+import java.io.BufferedReader
+import java.io.IOException
+import java.io.InputStreamReader
+
+class LicenseActivity : BaseActivity() {
+
+    @ContainerOptions(cache = CacheImplementation.NO_CACHE)
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setContentView(R.layout.activity_license)
+
+        setSupportActionBar(toolbar)
+        supportActionBar?.run {
+            setDisplayHomeAsUpEnabled(true)
+            setDisplayShowHomeEnabled(true)
+        }
+
+        setTitle(R.string.title_licenses)
+
+        loadFileIntoTextView(R.raw.apache, licenseApacheTextView)
+
+    }
+
+    override fun onOptionsItemSelected(item: MenuItem): Boolean {
+        when (item.itemId) {
+            android.R.id.home -> {
+                onBackPressed()
+                return true
+            }
+        }
+        return super.onOptionsItemSelected(item)
+    }
+
+    private fun loadFileIntoTextView(@RawRes fileId: Int, textView: TextView) {
+
+        val sb = StringBuilder()
+
+        val br = BufferedReader(InputStreamReader(resources.openRawResource(fileId)))
+
+        try {
+            var line: String? = br.readLine()
+            while (line != null) {
+                sb.append(line)
+                sb.append('\n')
+                line = br.readLine()
+            }
+        } catch (e: IOException) {
+            Log.w("LicenseActivity", e)
+        }
+
+        IOUtils.closeQuietly(br)
+
+        textView.text = sb.toString()
+
+    }
+
+}