feat: add fields with logx methods, support using third party logging libs. (#1847)

* backup

* simplify

* chore: remove unused pool

* chore: fix lint errors

* chore: use strings.Builder instead of bytes.Buffer

* test: add more tests

* chore: fix reviewdog

* test: fix data race

* feat: make logger customizable

* chore: fix reviewdog

* test: fix fails

* chore: fix set writer twice

* chore: use context instead of golang.org context

* chore: specify uint32 for level types

core/logx/util.go

@@ -0,0 +1,36 @@
+package logx
+
+import (
+	"fmt"
+	"runtime"
+	"strings"
+
+	"github.com/zeromicro/go-zero/core/timex"
+)
+
+func getCaller(callDepth int) string {
+	_, file, line, ok := runtime.Caller(callDepth)
+	if !ok {
+		return ""
+	}
+
+	return prettyCaller(file, line)
+}
+
+func getTimestamp() string {
+	return timex.Time().Format(timeFormat)
+}
+
+func prettyCaller(file string, line int) string {
+	idx := strings.LastIndexByte(file, '/')
+	if idx < 0 {
+		return fmt.Sprintf("%s:%d", file, line)
+	}
+
+	idx = strings.LastIndexByte(file[:idx], '/')
+	if idx < 0 {
+		return fmt.Sprintf("%s:%d", file, line)
+	}
+
+	return fmt.Sprintf("%s:%d", file[idx+1:], line)
+}