datatype and encoding should not be case sensitive

[csliuyb]

I can type int32 or INT32 and rle or RLE, which will make developers feel more confortable.

IoTDB> create timeseries root.vehicle.d0.s1
statement error: Statement format is not right:parsing error,statement: create timeseries root.vehicle.d0.s1 .message:line 1:36 mismatched input '' expecting WITH near 's1'. Please refer to SQL document and check if there is any keyword conflict.
IoTDB> create timeseries root.vehicle.d0.s1 with datatype=int32 encoding=rle
statement error: Statement format is not right:parsing error,statement: create timeseries root.vehicle.d0.s1 with datatype=int32 encoding=rle .message:line 1:57 missing , at 'encoding' near ''. Please refer to SQL document and check if there is any keyword conflict.
IoTDB> create timeseries root.vehicle.d0.s1 with datatype=int32,encoding=rle
statement error: data type int32 not support
IoTDB> create timeseries root.vehicle.d0.s1 with datatype=INT32,encoding=rle
statement error: encoding rle is not support
IoTDB> create timeseries root.vehicle.d0.s1 with datatype=INT32,encoding=RLE
execute successfully.