compile.sh might return an error und thus terminate make

compile.sh is designed to be used by other software systems too. For this
reason it should be installed along with binary executables.

gremlin.tex used pepi.sty and pepi.bst for which copyright is not fully
resolved. Replaced these entries with a standard bibtex style just to make
gremlin.tex compile outside my environment.

Point out potentially misleading results of the application of the convolution
function to time series being understood as cut-out of infinite functions.

The test cases provided here demonstrate that the convolution function
produces a (possibly unwanted) step response if one of the signals ends with a
finite value. This is theoretically correct, however might be unintended in
practical application.

Provide test plot T1Z.ps which focusses on the erroneous coda in the time
domain filter response when applying the taper prior to the filter.

Application of taper after filter removes the faulty signal, because taper has
length of original signal only, not of result of convolution operation.

This operation does not produce the expected results. Leave this to be fixed
later.

swapping order of filter an taper application makes faulty signal vanish

Convolve with delta pulse to delay by given time interval. To be used as a
test case for libtsxx convolve.h

The result of the libtsxx convolution operation appears unsatisfactory.
In order to test the library function I require a binary program to be
applied to test series. Since all other operations in cross.cc are identical
it appears reasonable to provide a convolution option in cross.cc

Also added: scaling with sampling interval

program is not experimental

and make tidesffx a standard target

missed to add two new files to the previous commit

Some issues of improper Fortran code are fixed. There are a many more
remaining (implicite type conversion with value truncation, unused labels,
unused variables, use of unititialized variable). I do not correct them here
since practically all of them affect the original 3rd-party code.

gfortran does not appreciate Hollerith code

Move programs for computation of tidal signals to subdirectory tides. Adjust
Makefile and list of directories with installable programs. Adjust README and
COPYING files also with respect to Seitosh layout.