Property printing

[stigrj]

Initialize properties to NaN, so that un-computed properties are not confused with zero value.

E.g. polarizability computed only in x and y directions=[1,1,0] will look like this

======================================================================
                            Polarizability
----------------------------------------------------------------------
 Wavelength            :           (nm)                    694.573171
 Frequency             :           (au)                      0.065600
                       :         (cm-1)                  14397.331226
----------------------------------------------------------------------
 Total tensor          :       1.668198       0.000000       0.000000
                       :       0.000000       1.668198       0.000000
                       :            N/A            N/A            N/A
 Isotropic average     :           (au)                           N/A
======================================================================

[codecov[bot]]

Codecov Report

Merging #270 into master will decrease coverage by 0.06%. The diff coverage is 6.66%.

@@            Coverage Diff             @@
##           master     #270      +/-   ##
==========================================
- Coverage   54.45%   54.39%   -0.07%     
==========================================
  Files         105      105              
  Lines        8309     8314       +5     
==========================================
- Hits         4525     4522       -3     
- Misses       3784     3792       +8     

Impacted Files	Coverage Δ
src/utils/print_utils.cpp	5.61% <0.00%> (-0.41%)	:arrow_down:
src/utils/math_utils.cpp	39.79% <16.66%> (-2.63%)	:arrow_down:

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[stigrj]

Rebased and readt to go