code cleanup using 'cppcheck'.

Corrected include paths ../trivia, ../readline.

Replaced by dependency on official libyaml-cpp0.3.

  rationale:
  - we accept that Frida will fail for array sizes > 2^15
  - we cannot exclude that complete conversion to size_t would
    cause underflow errors
warning -Wno-sign-compare
replace gsl_sort_index by new function triv::sorted_indices
initialize a few variables to prevent warning

result: no warnings from -pedantic, almost none from -Wall

declaring most indices as size_t
this will be reverted immediately

existing citations

moved ad-hoc routine RSSM:ReadSeries2Histo to arch/one-time-routines

This is the last version with 'rsh' ReadSeries2Histo.

eliminate CListIter, obsolete since long.

PSpec S becomes s.

Refactored; basics moved to libtrivia

  exe/ls-includes.rb

cleanup: rm cv_intmode