added .gitignore

.gitignore

+# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio and Webstorm
+# Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
+
+# User-specific stuff:
+.idea/**/workspace.xml
+.idea/**/tasks.xml
+.idea/dictionaries
+
+# Sensitive or high-churn files:
+.idea/**/dataSources/
+.idea/**/dataSources.ids
+.idea/**/dataSources.xml
+.idea/**/dataSources.local.xml
+.idea/**/sqlDataSources.xml
+.idea/**/dynamic.xml
+.idea/**/uiDesigner.xml
+
+# Gradle:
+.idea/**/gradle.xml
+.idea/**/libraries
+
+# CMake
+cmake-build-debug/
+
+# Mongo Explorer plugin:
+.idea/**/mongoSettings.xml
+
+## File-based project format:
+*.iws
+
+## Plugin-specific files:
+
+# IntelliJ
+/out/
+
+# mpeltonen/sbt-idea plugin
+.idea_modules/
+# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio and Webstorm
+# Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
+
+# User-specific stuff:
+*.iml
+.idea/**
+.idea/**/workspace.xml
+.idea/**/tasks.xml
+.idea/dictionaries
+
+# Sensitive or high-churn files:
+.idea/**/dataSources/
+.idea/**/dataSources.ids
+.idea/**/dataSources.xml
+.idea/**/dataSources.local.xml
+.idea/**/sqlDataSources.xml
+.idea/**/dynamic.xml
+.idea/**/uiDesigner.xml
+
+# Gradle:
+.idea/**/gradle.xml
+.idea/**/libraries
+
+# CMake
+cmake-build-debug/
+
+# Mongo Explorer plugin:
+.idea/**/mongoSettings.xml
+
+## File-based project format:
+*.iws
+
+## Plugin-specific files:
+
+# IntelliJ
+/out/
+
+# mpeltonen/sbt-idea plugin
+.idea_modules/
+
+# JIRA plugin
+atlassian-ide-plugin.xml
+
+# Cursive Clojure plugin
+.idea/replstate.xml
+
+# Crashlytics plugin (for Android Studio and IntelliJ)
+com_crashlytics_export_strings.xml
+crashlytics.properties
+crashlytics-build.properties
+fabric.properties# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio and Webstorm
+                 # Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
+
+                 # User-specific stuff:
+                 .idea/**/workspace.xml
+                 .idea/**/tasks.xml
+                 .idea/dictionaries
+
+                 # Sensitive or high-churn files:
+                 .idea/**/dataSources/
+                 .idea/**/dataSources.ids
+                 .idea/**/dataSources.xml
+                 .idea/**/dataSources.local.xml
+                 .idea/**/sqlDataSources.xml
+                 .idea/**/dynamic.xml
+                 .idea/**/uiDesigner.xml
+
+                 # Gradle:
+                 .idea/**/gradle.xml
+                 .idea/**/libraries
+
+                 # CMake
+                 cmake-build-debug/
+
+                 # Mongo Explorer plugin:
+                 .idea/**/mongoSettings.xml
+
+                 ## File-based project format:
+                 *.iws
+
+                 ## Plugin-specific files:
+
+                 # IntelliJ
+                 /out/
+
+                 # mpeltonen/sbt-idea plugin
+                 .idea_modules/
+
+                 # JIRA plugin
+                 atlassian-ide-plugin.xml
+
+                 # Cursive Clojure plugin
+                 .idea/replstate.xml
+
+                 # Crashlytics plugin (for Android Studio and IntelliJ)
+                 com_crashlytics_export_strings.xml
+                 crashlytics.properties
+                 crashlytics-build.properties
+                 fabric.properties
+# JIRA plugin
+atlassian-ide-plugin.xml
+
+# Cursive Clojure plugin
+.idea/replstate.xml
+
+# Crashlytics plugin (for Android Studio and IntelliJ)
+com_crashlytics_export_strings.xml
+crashlytics.properties
+crashlytics-build.properties
+fabric.properties
+
+.project
+.classpath
+.settings
+
+
+#maven build target
+target/