aliases is a list of string aliases for the given denom
denom represents the string name of the given denom unit (e.g uatom).
exponent represents power of 10 exponent that one must raise the base_denom to in order to equal the given DenomUnit's denom 1 denom = 10^exponent base_denom (e.g. with a base_denom of uatom, one can create a DenomUnit of 'atom' with exponent = 6, thus: 1 atom = 10^6 uatom).
DenomUnit represents a struct that describes a given denomination unit of the basic token.