Remove constructor and overloads using Boost ptime. Also remove methods
rendered obsolete by the removal of ptime dependency. Rename methods
whose name was initially set to differentiate from ptime counterparts,
an example of which being 'timeTFromEclipse' renamed to
'timeFromEclipse'.
Replace use of gmtime() with util_set_date_values_utc().
Change signature of addTStep(std::time_t) to addTStep(int64_t).
Change base of month indices returned from eclipseMonthIndices(). Now
indices are 1-based.
Simplify timeFromEclipse() (previously timeTFromEclipse()).
Add mkdatetime(), analogous to mkdate() but with also hour, minute
and second parameters.
47bfce0f3a