Added a complex comparison sample scenario.
Moved Semantic Comparison sample classes

to sub-folder, and made them public. The next step is to make them
extensible with Constructor Injection, so that each of them are decoupled
from the other. This will (hopefully) better demonstrate how a loosely
coupled system can be built.
Opened SemanticElementComparer for extensions.
Made SemanticReflectionVisitor looser,

because there was no reason it had to expose a strongly typed sequence of
comparison values in order to do its work.
Added value collection sample.
Changed Value Collection sample to use TimeSpan,

as this may be easier to understand, and better demonstrates the ability
to collect values from both properties and fields.
Added a problem description to the readme.
Added target audience to readme file.
Added initial example code.
Added value-collection code examples.
Corrected a typo.
Changed from Setext to Atx-style headers,

in order to be able to use more than two levels of headers.
Added a third-level header,

because more sample code that demonstrates other scenarios will follow.
Added value assignment sample code to readme.
Added sample code for writing values from Visitor.
Slightly refactored sample test code,

in order to make it more explicit what's going on when you read the code
outside of an IDE (e.g. on GitHub).