Load properties from the provided stream, via a foreach.

We use an iterator to sweep text lines, and extract lValue and rValue pairs from each one, The expected file format is as follows:

x = y
abc = 123
x.y.z = this is a single property
this is a comment line

Note that the provided name and value are actually slices and should be copied if you intend to retain them (using name.dup and value.dup where appropriate.)