1. Rederive and correct discretization of h(t)=a^6/(t+a)^7. We need double integration via t instead of single.
   Implement this correction into computer program.
2. Describe how preliminary estimation of BER is done in program.
   Work began in definitions_estimations_PAPM.png
   Inaccurately done in PAPM_optimal_parameters.png
   Should use the final formula from PAPPM_Perr_small_noises2.png
3. Make notations consistent trough the framework:
   1. PAPPM_Perr_0.png ... Z-->z
                           Note C =/= Alphabet capacity.
   2. Remove redundant definitions from "correlation" section.
4. Merge "Correlation" and "Model Description. BER." sections.