replaces .hgignore with .gitignore and add Xcode and macOS related ignores

.gitignore

@@ -0,0 +1,70 @@
+# Xcode
+
+## Build generated
+build/
+DerivedData/
+
+## Various settings
+*.pbxuser
+!default.pbxuser
+*.mode1v3
+!default.mode1v3
+*.mode2v3
+!default.mode2v3
+*.perspectivev3
+!default.perspectivev3
+xcuserdata/
+
+## Other
+*.moved-aside
+*.xccheckout
+*.xcscmblueprint
+
+## Obj-C/Swift specific
+*.hmap
+*.ipa
+*.dSYM.zip
+*.dSYM
+
+## Playgrounds
+timeline.xctimeline
+playground.xcworkspace
+
+## Swift Package Manager
+# Add this line if you want to avoid checking in source code from Swift Package Manager dependencies.
+# Packages/
+# Package.pins
+# Package.resolved
+.build/
+
+## Xcode Patch ###
+**/xcshareddata/WorkspaceSettings.xcsettings
+
+# macOS
+
+## General
+.DS_Store
+.AppleDouble
+.LSOverride
+
+## Icon must end with two \r
+Icon
+
+## Thumbnails
+._*
+
+## Files that might appear in the root of a volume
+.DocumentRevisions-V100
+.fseventsd
+.Spotlight-V100
+.TemporaryItems
+.Trashes
+.VolumeIcon.icns
+.com.apple.timemachine.donotpresent
+
+## Directories potentially created on remote AFP share
+.AppleDB
+.AppleDesktop
+Network Trash Folder
+Temporary Items
+.apdisk

.hgignore

@@ -1,6 +0,0 @@
-regexp
-\.DS_Store
-xcuserdata/.*
-\.orig$
-\.git/
-\.gitkeep