satisfies(
version,constraint) ->ok
Check whether a version satisfies a constraint
Returns true if version satisfies constraint. A nil or empty
constraint matches anything. A bare version (no operator) is treated as
>=. Supported operators: >=, >, <=, <, =, and ~>
(pessimistic: ~>1.2 means >=1.2.0 <2.0.0; ~>1.2.3 means
>=1.2.3 <1.3.0).