Add line endings normalization
Add line endings normalization

Since template files (Assets/Terasurware/Editor/EntityTemplate*.txt) have `\n` (0x0a) as line ending, output of ExcelImporterMaker contains different line endings (`0x0a` for template part, `0x0d,0x0a` for generated part(`StringBuilder.AppendLine()`)) in Windows environment.
This changeset fixes it by normalizing and replacing line endings properly.

tsubaki/Unity-Excel-Importer-Maker