Add support for just one constructor

Change-Id: I9a26894feddb74fb9d9453d71c10120ab3dfbe08
Add support for default values in constructor parameters

Change-Id: I8fd1e0f900c0e88839f3827d9b7db7cccd8f4fca
Prune core.kmd.json to contain only core elements description

Change-Id: If376ab4dd46af903a96ca9ae6b8328774ca4d987