add gitignore

.gitignore

@@ -0,0 +1,45 @@
+
+# Created by https://www.gitignore.io/api/intellij,sbt,scala
+
+### Intellij ###
+# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio and Webstorm
+# Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
+.idea/
+
+### Intellij Patch ###
+# Comment Reason: https://github.com/joeblau/gitignore.io/issues/186#issuecomment-215987721
+
+# *.iml
+# modules.xml
+# .idea/misc.xml
+# *.ipr
+
+
+### SBT ###
+# Simple Build Tool
+# http://www.scala-sbt.org/release/docs/Getting-Started/Directories.html#configuring-version-control
+
+target/
+lib_managed/
+src_managed/
+project/boot/
+.history
+.cache
+
+
+### Scala ###
+*.class
+*.log
+
+# sbt specific
+.lib/
+dist/*
+project/plugins/project/
+
+# Scala-IDE specific
+.scala_dependencies
+.worksheet
+
+# ENSIME specific
+.ensime_cache/
+.ensime