feat: make projects available for netstandard 2.1

chore: update nosfiles package

chore: add repository url and license to nuget

Merge pull request #22 from Rutherther/data

Add NosTale data information

chore(data): add short descriptions of projects

feat(data): add .nos files parsing support

feat(data): add .NOS file readers

feat(data): add skeleton for NosTale data