Promote Atto parser as a module

CHANGELOG.md

@@ -1,5 +1,16 @@
 # Cron4s Change Log
 
+## 0.8.0
+
+Breaking changes:
+
+* In previous versions, Cron expression parsing was using [Scala Parser Combinators](https://github.com/scala/scala-parser-combinators).
+  Parsing is now achieved using [Atto library](https://tpolecat.github.io/atto/) by default on all targets except Native.
+  Both parsers should behave the same way and the API didn't change. They will be kept in sync for the time being.
+  In case you notice any change in behavior, please open an issue with your input.
+  You can always fall back to the Parser Combinator version by adding `cron4s-parserc` as a dependency of your project and
+  use `Cron.withParser(cron4s.parsing.Parser)` instead of `Cron` instance.
+
 ## 0.6.1
 
 Bug fixes

bench/src/main/scala/cron4s/bench/ParserBenchmark.scala

@@ -17,11 +17,11 @@
 package cron4s.bench
 
 import java.util.concurrent.TimeUnit
-
 import cron4s._
-
 import org.openjdk.jmh.annotations._
 
+import scala.annotation.nowarn
+
 @State(Scope.Thread)
 @BenchmarkMode(Array(Mode.AverageTime))
 @OutputTimeUnit(TimeUnit.MICROSECONDS)
@@ -37,9 +37,10 @@ class ParserBenchmark {
   )
   var cronString: String = _
 
+  @nowarn("cat=deprecation")
   @Benchmark
-  def parserCombinators() = parsing.parse(cronString)
+  def parserCombinators() = parsing.Parser.parse(cronString)
 
   @Benchmark
-  def attoParser() = atto.parse(cronString)
+  def attoParser() = atto.Parser.parse(cronString)
 }