context CHANGE refactor ietf-yang-library operations
context CHANGE refactor ietf-yang-library operations

Use generic functions to work with schema and data tree and avoid
code duplication.

PavolVican/libyang,PavolVican/libyang,PavolVican/libyang,lukasmacko/libyang,PavolVican/libyang,lukasmacko/libyang,PavolVican/libyang