refactor to avoid panic

[hangxie]

parquet-go as a library should avoid panic so application can decide what to do with exceptions, some panic conditions can be avoided by carefully check data (eg xitongsys/parquet-go-source#31):

$ egrep -r 'recover\(\)|panic\(' *
common/common.go:				panic(err)
common/common.go:				panic(err)
common/common.go:				panic(fmt.Errorf("Unknown repetitiontype: '%v'", val))
common/common.go:				panic(fmt.Errorf("Unknown keyrepetitiontype: '%v'", val))
common/common.go:				panic(fmt.Errorf("Unknown valuerepetitiontype: '%v'", val))
common/common.go:				panic(fmt.Errorf("Unknown encoding type: '%v'", val))
common/common.go:				panic(fmt.Errorf("Unknown keyencoding type: '%v'", val))
common/common.go:				panic(fmt.Errorf("Unknown valueencoding type: '%v'", val))
common/common.go:				panic(fmt.Errorf("Unrecognized tag '%v'", key))
common/common.go:		panic("type " + info.Type + ": " + err.Error())
common/common.go:				panic("logicaltype time error")
common/common.go:				panic("logicaltype time error")
common/common.go:			panic("unknow logicaltype: " + val)
common/common.go:	panic("No known func table in FindFuncTable")
common/common.go:		panic(err)
common/common.go:		panic(err)
layout/rowgroup.go:				if r := recover(); r != nil {
marshal/marshal.go:		if r := recover(); r != nil {
marshal/unmarshal.go:		if r := recover(); r != nil {
marshal/json.go:		if r := recover(); r != nil {
schema/schemahandler.go:		if r := recover(); r != nil {
schema/json.go:		if r := recover(); r != nil {
writer/writer.go:				if r := recover(); r != nil {
writer/writer.go:						panic(errors.New("unsupported data page: " + page.Header.String()))