moved construct_discrete_edge_matrix to common

[corochann]

Because this function may be used in other preprocessor.

[corochann]

Added no-compat because the method's namespace will be changed.

[codecov-io]

Codecov Report

Merging #260 into master will increase coverage by 0.4%. The diff coverage is 90.69%.

@@            Coverage Diff            @@
##           master     #260     +/-   ##
=========================================
+ Coverage   82.22%   82.63%   +0.4%     
=========================================
  Files         112      112             
  Lines        5491     5504     +13     
=========================================
+ Hits         4515     4548     +33     
+ Misses        976      956     -20