Send manga/chapter/page details when sharing a chapter page

closes #443
Also for page_ string, removing the colon in it

app/src/main/java/eu/kanade/tachiyomi/ui/reader/ReaderActivity.kt

@@ -645,9 +645,15 @@ class ReaderActivity : BaseRxActivity<ReaderPresenter>(),
      * Called from the presenter when a page is ready to be shared. It shows Android's default
      * sharing tool.
      */
-    fun onShareImageResult(file: File) {
+    fun onShareImageResult(file: File, page: ReaderPage) {
+        val manga = presenter.manga ?: return
+        val chapter = page.chapter.chapter
+
+        val text = "${manga.title}: ${chapter.name}, ${getString(R.string.page_, page.number)}"
+
         val stream = file.getUriCompat(this)
         val intent = Intent(Intent.ACTION_SEND).apply {
+            putExtra(Intent.EXTRA_TEXT, text)
             putExtra(Intent.EXTRA_STREAM, stream)
             flags = Intent.FLAG_ACTIVITY_NEW_TASK or Intent.FLAG_GRANT_READ_URI_PERMISSION
             clipData = ClipData.newRawUri(null, stream)

app/src/main/java/eu/kanade/tachiyomi/ui/reader/ReaderPresenter.kt

@@ -572,7 +572,7 @@ class ReaderPresenter(
             .subscribeOn(Schedulers.io())
             .observeOn(AndroidSchedulers.mainThread())
             .subscribeFirst(
-                { view, file -> view.onShareImageResult(file) },
+                { view, file -> view.onShareImageResult(file, page) },
                 { _, _ -> /* Empty */ }
             )
     }

app/src/main/res/values/strings.xml

@@ -268,7 +268,7 @@
     <string name="set_as_cover">Set as cover</string>
     <string name="set_as_default_for_all">Set as default for all</string>
     <string name="cover_updated">Cover updated</string>
-    <string name="page_">Page: %1$d</string>
+    <string name="page_">Page %1$d</string>
     <string name="next_chapter_not_found">Next chapter not found</string>
     <string name="decode_image_error">The image could not be decoded</string>
     <string name="use_image_as_cover">Use this image as cover art?</string>