Convert :source-api and :source-local to android library module (#3636)

- There's really no plan to support other platforms on this code base
- The "KMP" modules only had android target which is rather pointless
- `i18n` involves more work but given it has no actual code keeping it as is

source-api/src/main/kotlin/eu/kanade/tachiyomi/util/JsoupExtensions.kt

@@ -0,0 +1,26 @@
+package eu.kanade.tachiyomi.util
+
+import okhttp3.Response
+import org.jsoup.Jsoup
+import org.jsoup.nodes.Document
+import org.jsoup.nodes.Element
+
+fun Element.selectText(css: String, defaultValue: String? = null): String? {
+    return select(css).first()?.text() ?: defaultValue
+}
+
+fun Element.selectInt(css: String, defaultValue: Int = 0): Int {
+    return select(css).first()?.text()?.toInt() ?: defaultValue
+}
+
+fun Element.attrOrText(css: String): String {
+    return if (css != "text") attr(css) else text()
+}
+
+/**
+ * Returns a Jsoup document for this response.
+ * @param html the body of the response. Use only if the body was read before calling this method.
+ */
+fun Response.asJsoup(html: String? = null): Document {
+    return Jsoup.parse(html ?: body.string(), request.url.toString())
+}

source-api/src/main/kotlin/eu/kanade/tachiyomi/util/RxExtension.kt

@@ -0,0 +1,6 @@
+package eu.kanade.tachiyomi.util
+
+import rx.Observable
+import tachiyomi.core.common.util.lang.awaitSingle
+
+suspend fun <T> Observable<T>.awaitSingle(): T = awaitSingle()