ncm-mkgridmap: use CAF::Process instead of backticks + misc. cleanups

Commands to execute are part of the configuration and must be tokenized to avoid a subshell. This implementation contains a rudimentary tokenizer. Should such an (improved) tokenized be part of `CAF::Process`  rather than having all components with a similar problem reinventing the wheel...??? (#38 is another example).

If I find the time before 14.10, I'd like to remove the use of `LC::Check` and `NCM::Check`` but no warranty... open a new issue if merged before this is done.