Develop configfile commands

Functions to manipulate easily the configuration file.

See merge request !48

Add hadcm3dec

Add the possibility of loading the second set of HadCM3 decadal data (i3p1)

Modification of Corr to accomodate ranked correlation

Could you please make sure I didn't screw this up.

Thx.

@nevensf
@mmenegoz

Develop load esa

Changes in path for ESA and E-OBS data for /cfunas structure. Please merge :)

Develop load esa

Added line to load ESA tos and sic into IC3.conf. No testing needed