Feature #2801 warnings (#2802)

* Per #2801, add new time_offset_warning config option.

* Per #2810, update MetConfig class to parse and check the time_offset_warning config option.

* Per #2801, update Grid-Stat, MODE, PCP-Combine, Series-Analysis, Wavelet-Stat, and the WWMCA tool to call MetConfig::time_offset_warning() to decide whether to print a Warning or Debug(3) log message about initialization or valid time differences.

* Per #2801, no change to content. Just removing unneeded whitespace.

* Per #2801, remove extra empty line foromw m warning message.

* Per #2801, remove extra empty line from MODE warning messages.

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Co-authored-by: MET Tools Test Account <met_test@seneca.rap.ucar.edu>

data/config/ConfigConstants

@@ -7,6 +7,9 @@
 // Warning message results in tool exiting.
 exit_on_warning = FALSE;
 
+// Allowable offset in seconds to silence time difference warning messages
+time_offset_warning = 0;
+
 // NetCDF Compression per variable (0 to 9, 0: disable compression)
 // This will be overridden by the environment variable MET_NC_COMPRESS and the
 // command line argument.