Struct support, performance improvements

• Immutable structs can now be used, you are no longer restricted to classes
• We no longer throw NSError-based errors, they're all enum ObjectBoxError now
• Strings that were created as NSStrings previously are now created as Swift Strings, which should reduce the number of unnecessary UTF-16/UTF-8 roundtrip conversions when Swift 5.1 arrives
• New projects are now set up with separate generated source files for each target by setup.rb.
• Binaries: Swift 5 ABI only

Swift 5 support, build improvements

• Binaries: Swift 5 ABI only
• ObjectBox setup script can now also be used without CocoaPods
• ObjectBox can now be used in frameworks

Model Migration

• Your data model is now migrated transparently for you when you make changes
• Properties can be indexed
• You can require property fields to be unique
• You can specify a different name for use in the model than the instance variable's
• Use of ObjectBox without CocoaPods has been simplified
• You do not need to annotate back-links in relations anymore in clear cases
• Binaries: Swift 4 ABI only.

Alpha 6

• Remove limitations on order of conventional properties vs. relations in codegen
• Support sandboxed macOS applications (see ObjectBox docs on macOS sandbox setup)
• Add annotations for transient properties.

Alpha 5

• More code generation fixes for optionals
• Pushed expanded example app that demos optionals
• Fixes for transfer of decoded dates to entities

Alpha 3

Sandboxing fixes, quality-of-life improvements and others.

Alpha

v0.5.1

README.md: add setup.rb for example setup