add gitignore

.gitignore.txt

+# Modified from:
+#     https://github.com/github/gitignore/blob/master/Unity.gitignore
+
+/[Ll]ibrary/
+/[Uu]serSettings/
+[Tt]emp/
+[Oo]bj/
+/[Bb]uild/
+/[Bb]uilds/
+/[Ll]ogs/
+/[Mm]emoryCaptures/
+
+# Uncomment this line if you wish to ignore the asset store tools plugin
+# [Aa]ssets/AssetStoreTools*
+
+# Visual Studio cache directory
+.vs/
+
+# Gradle cache directory
+.gradle/
+
+# Autogenerated VS/MD/Consulo solution and project files
+ExportedObj/
+.consulo/
+*.csproj
+*.unityproj
+*.sln
+*.suo
+*.tmp
+*.user
+*.userprefs
+*.pidb
+*.booproj
+*.svd
+*.pdb
+*.mdb
+*.opendb
+*.VC.db
+
+# Unity3D generated meta files
+*.pidb.meta
+*.pdb.meta
+*.mdb.meta
+
+# Unity3D generated file on crash reports
+sysinfo.txt
+
+# Crashlytics generated file
+crashlytics-build.properties
+
+# Windows
+Thumbs.db
+Thumbs.db.meta
+
+# MacOS
+*.DS_Store
+
+# VS Code
+*.vscode
\ No newline at end of file