fix: fix bug when creating big projects

In the case of very big projects classes proji would break with an error
that reported that too many files were opened at the same time.

Until now files were created with os.OpenFile() which creates files if
they don't already exist and then opens them for editing or reading. The
editing/reading part is obviously unnecessary for proji anyways. Now
files are created with os.Create() which is generally more fitting and
seems to solve the issue with unclosed file handles. The file handles
are now closed explicitly too.

Fixes #110

pkg/proji/storage/item/project.go

@@ -106,10 +106,13 @@ func (proj *Project) createFiles() error {
 
 		// Replace keyword with project name
 		file.Destination = re.ReplaceAllString(file.Destination, proj.Name)
-		_, err := os.OpenFile(file.Destination, os.O_RDONLY|os.O_CREATE, os.ModePerm)
+
+		// Create file
+		f, err := os.Create(file.Destination)
 		if err != nil {
 			return err
 		}
+		_ = f.Close()
 	}
 	return nil
 }