Revision 38

Extracted ASCII art from "inigeom" into a separate text file in the
documentation.

"test_disvert" now creates a separate file for layer thicknesses.

Moved variables from module "yomcst" to module "suphec_m" because this
is where those variables are defined. Kept in "yomcst" only parameters
of Earth orbit. Gave the attribute "parameter" to some variables of
module "suphec_m".

Variables of module "yoethf" were defined in procedure "suphec". Moved
these definitions to a new procedure "yoethf" in module "yoethf_m".