Adding UInt8 and Integer16 CDS types (WIP)

[Fannon]

Added

• Added cds.Integer16 type (signed integer with 16 bit)
• Added cds.UInt8 type (unsigned integer with 8 bit)

TODO

• Also add this in the existing two type mappings
• Follow up task: Create HANA mapping ?
• Clarify: Int16 vs Integer16?
• Clarify: Should we breaking change rename Integer64 to Int64 for CAP CDS Type consistency?

[Fannon]

TODO: Is this Int16 (CAP) or Integer16, consistent with existing Integer64?

[Fannon]

Suggested change

	- "cds.Integer16"
	- "cds.Int16"

[Fannon]

TODO: Clarify - should this have been cds.Int64 ? Then we can also go with cds.Int16.

Then we'd be consistent with https://cap.cloud.sap/docs/guides/domain-modeling#standard-built-in-types

[Fannon]

We confirmed that Integer64 is already in use we cannot just drop it. In best case we have to deprecate it, but keep it.

We can also not introduce this PR change without FIRST:

• Define the mappings
• Ecosystem supports the new mappings

Only after the ecosystem is ready for the new types, we should merge and release this.