Improved diff algorithm for XML and TEXT/curly, replaced UNIX diff with structural in-mem algorithm
Fixed: ["show compare" and "show compare | display cli" differs #23](https://github.com/clicon/clixon-controller/issues/23)
Changed parameters of example clispec function `compare_dbs()`
Added show2cbuf functions for TEXT/CLI
Renamed clixon_txt2file to clixon_text2file
