All types of whitespace characters used for delineation are not correctly parsed in input files

[vtripath65]

When locating blocks in put file, previously a tab was not being considered as a space.

Now, if a line contains only tabs and/or spaces its considered an empty line.

The issues in the test set related to external charges with a tab at the end of the file as a newline is now fixed.

[ohearnk]

To summarize, it was discovered by @vtripath65 and @agoetz that tab characters are present and not correctly parsed in the following inputs for gradient tests:

• test/grad_naip_meoh_libxc_pbeh_def2svp.in
• test/grad_naip_meoh_libxc_pbeh_sto3g.in
• test/grad_ncnaip_b3lyp_631gss.in
• test/grad_ncnaip_b3lyp_sto3g.in
• test/grad_rpsb_meoh_rhf_321g.in
• test/grad_rpsb_meoh_rhf_sto3g.in

This mistake leads to the number of number of external point charges being incorrect, which also leads to issues with point charge gradients (which were being computed for non-existent point charges).

This also is the underlying bug which is causing the gradient test failures in #403.

Lastly, note it is likely advisable to replace the routines in src/subs with more modern and widely tested alternatives in order to avoid future issues like this one. The community-driven Fortran standard library project might be a good choice if it covers all the routines used in QUICK.

[agoetz]

Looks good to me. Thanks.