Create wrapper for tc_gen app

[georgemccabe]

MET GitHub ticket 1127 (dtcenter/MET#1127) involves writing a new tool. We will eventually want to wrap this tool in METplus. There are components of TcPairs wrapper that can be utilized in this wrapper as well, such as the code to reformat extra tropical cyclone data into ATCF format. When development for the TcGen wrapper begins, we should create a parent class called TcWrapper or something similar that can contain common configuration reading (use self.app_name to determine which variable to read) and reformatting code so that it can be used by both TcGen and TcPairs wrappers.

This tool uses many of the same functionality as TC-Stat. Usage includes:

Usage: tc_gen
-genesis path
-track path
-config file
[-out base]
[-log file]
[-v level]

The -genesis option is basically the forecasted tracker file that has genesis events and must be used at least once but can be used several times.
The -track option can be used to read in both Bdeck (best track) and/or Adeck CARQ (operational analysis) files and must be used at least once but can be used several times.

Other differences appear to be:
fcst_genesis = {
vmax_thresh = NA;
mslp_thresh = NA;
}

best_genesis = {
technique = "BEST";
category = [ "TD", "TS" ];
vmax_thresh = NA;
mslp_thresh = NA;
}
oper_genesis = {
technique = "CARQ";
category = [ "DB", "LO", "WV" ];
vmax_thresh = NA;
mslp_thresh = NA;
}

genesis_window = {
beg = -24;
end = 24;
}

genesis_radius = 300;

Due Date: METplus 4.0 beta 1or METplus v3.1 if at all possible...

Account:
7790971

[georgemccabe]

Created feature branch feature_278_tc_gen with start of wrapper.