Add Hentai2Read (hentai2read.com) source. (#46)

* Add Hentai2Read (hentai2read.com) source.

* Convert sch_flt_in and sch_flt_out to camelCase.

* Combine tag selectors in mangaDetailsParse().

* Move Pattern.compile() call to companion object to avoid repeated initialization.

* Move constant String imageBaseUrl to companion object.

* Make parseChapterDate() a little more compact.

* Refactor things to avoid unnecessary string splitting and calls to Elements.first().

* Remove implicit return and implicit return type from popularMangaRequest() and latestUpdatesRequest().

* Trim whitespace from string before parsing chapter date.

* Update POST params and change how tags are included/excluded.

* Add CharacterName and CharacterNameSelect filters.

* Add TagSearchMode filter.

* Change TagList to have title, to prepare for different groups of tags.

* Change TagList in FilterList to use new title.

* Add category list.

* Change tag list.

* Add doujin list.

* Update FilterList to include new filters.

* Add Gson and Kotson dependencies.

* Fix searching, now compute base64-encoded string to use in URL.

* Remove all code used to manually compute base64 string in URL.

* Add searchMangaParse override, store base64String if there is a next page in search.

* Remove unnecessary url val, left over from debug.

* Update tag list.

* Update doujin list.

* Update comments showing number of tags/doujins in TagList.

* Remove unnecessary tags var in mangaDetailsParse, can build manga.genre directly from list.

src/en/hentai2read/build.gradle

@@ -0,0 +1,13 @@
+apply plugin: 'com.android.application'
+apply plugin: 'kotlin-android'
+
+ext {
+    appName = 'Tachiyomi: Hentai2Read'
+    pkgNameSuffix = 'en.hentai2read'
+    extClass = '.Hentai2Read'
+    extVersionCode = 1
+    extVersionSuffix = 1
+    libVersion = '1.0'
+}
+
+apply from: "$rootDir/common.gradle"