Refine comments in parsesyslog.go code

Enhanced the clarity and accuracy of method descriptions in the parsesyslog.go file. This includes detailing exact function purposes (such as for Register and New) and improving interface definitions (like Parser).

parsesyslog.go

@@ -20,7 +20,7 @@ var (
 	types = map[ParserType]func() (Parser, error){}
 )
 
-// Parser defines the interface for parsing different types of Syslog messages
+// Parser is an interface for parsing log messages.
 type Parser interface {
 	ParseReader(io.Reader) (LogMsg, error)
 	ParseString(s string) (LogMsg, error)
@@ -29,7 +29,8 @@ type Parser interface {
 // ParserType is a type of parser for logs messages
 type ParserType string
 
-// Register does something
+// Register registers a new ParserType with its corresponding
+// Parser function.
 func Register(t ParserType, fn func() (Parser, error)) {
 	lock.Lock()
 	defer lock.Unlock()
@@ -40,7 +41,13 @@ func Register(t ParserType, fn func() (Parser, error)) {
 	types[t] = fn
 }
 
-// New returns a new Parser based on the given parameter
+// New returns a Parser of the specified ParserType and an error.
+// It looks up the ParserType in the types map and if found,
+// calls the corresponding Parser function to create a new Parser
+// instance.
+//
+// If the ParserType is not found in the map, it returns nil
+// and ErrParserTypeUnknown.
 func New(t ParserType) (Parser, error) {
 	p, ok := types[t]
 	if !ok {