lnd: bump version to 0.2.1-alpha
lnd: bump version to 0.2.1-alpha

LightningNetwork/lnd,ddustin/lnd,ddustin/lnd,aakselrod/lnd,AndrewSamokhvalov/lnd,LightningNetwork/lnd,AndrewSamokhvalov/lnd,aakselrod/lnd