fixed clearing values and add other color for calculated fields
Merge pull request #1 from pmezykowski/feature/fixing_clear_calculated_values_in_caluclation_tab

fixed clearing values and add other color for calculated fields
load fixed by refreshing model list from db; save fixed by join db query string in classic way (without built-in anti-injection mechanism)
Merge pull request #2 from pmezykowski/feature/fixing_problems_with_save_and_load

Feature/fixing problems with save and load