[App] App target setup (#1)

This PR contains the work done to set the `App` target for the **Reviews** project.

Reviewed-on: rock-n-code/app-reviews#1
Co-authored-by: Javier Cicchelli <javier@rock-n-code.com>
Co-committed-by: Javier Cicchelli <javier@rock-n-code.com>

.gitignore

@@ -0,0 +1,24 @@
+### Swift ###
+# Xcode
+## User settings
+xcuserdata/
+
+## compatibility with Xcode 8 and earlier (ignoring not required starting Xcode 9)
+*.xcscmblueprint
+*.xccheckout
+
+## Obj-C/Swift specific
+*.hmap
+
+## App packaging
+*.ipa
+*.dSYM.zip
+*.dSYM
+
+## Playgrounds
+timeline.xctimeline
+playground.xcworkspace
+
+### SwiftPM ###
+Packages
+*.xcodeproj