Merge pull request #5 from Lozov-Petr/model

BugFix: check fields on null.
Merge pull request #7 from ladagagina/master

Excel Export
Move Interfaces.fs
Remade all conflicts using LINQ.
Add conflict of blank fields in enum conflicts.
Merge pull request #8 from Lozov-Petr/model

Remade conflicts using LINQ.
Import to Excel