Fix clean required when switching between Simulator/Device

When an app that uses OAuth2Client is built to run in the simulator, then re-built to run on a device (or vice-versa), XCode's linker gives an error about ignoring the file:
`Ignoring file [...]/Build/Products/Debug-iphoneos/libOAuth2Client.a, file was built for archive which is not the architecture being linked (armv7):[...]/Build/Products/Debug-iphoneos/libOAuth2Client.a`.

The only way around this, currently, is to clean the project.

This appears to be happening because in the target build settings, `Deployment Location` is set to `YES`, which causes a symlink to be created in the build directory (instead of putting the library there directly). This symlink is not updated/rebuilt when switching between device and simulator builds.

Changing `Deployment Location` to `NO` removes the need to clean when switching between device and simulator builds.