Add support for the `org.osbuild.inline` source via a new `InlineSource`
and the corresponding `InlineSourceItem`. A utility function `AddItem`
can be used to conveniently add items based on data (as strings).
Adding new types and adapting copies of all the old types to match the
new Manifest schema:
New types:
- Stages
- org.osbuild.ostree.init
- org.osbuild.ostree.pull
- org.osbuild.ostree.preptree (replaces org.osbuild.rpm-ostree)
- org.osbuild.curl
- Converted from assemblers
The concept of a Build and Assembler stage in gone now. Instead they
are regular Stages like any other.
- org.osbuild.oci-archive
- org.osbuild.ostree.commit
- Sources
- org.osbuild.curl
- org.osbuild.ostree
- Inputs
- org.osbuild.files
- org.osbuild.ostree
Types with changes:
- Stages
- org.osbuild.rpm:
- New input structure for defining packages
- New options
Basically copies:
- The rest simply rename the `Name` field to `Type`
Decoding types with interface fields:
Types that contain interfaces with multiple implementations implement
their own UnmarshalJSON method. In these cases, we use a JSON decoder
with the `DisallowUnknownFields` option to catch errors during the
deserialization while trying to determine which implementation matches
the data.
Copied tests for copied types are adapted accordingly.
