fixed a bug HashType when converting a value; the fix just tests the value to ensure it is a hexadecimal string rather than converting the value to the a long integer.  Without this fix, the final assertion in test_md5_type in test_serialize.py fails
Found some tests that appear to ensure broken behavior.  Updated and code fixes are coming.
Found another test that appears to rely on broken behavior.
Updated tests to use explicitly mentioned roles and to fix type coercion bugs after serialization.
This commit represents a big changeset that consolidates the serialization on
top of `apply_shape`.

The concept of `apply_shape` is local to the `MultiType` classes.  I now feel
the name `MultiType` is confusing and I might change it to `CompoundType`, to
make the intent more obvious.  `apply_shape` is applied to compound types
because we can't be sure if the compound type has types or models in it. The
new recursion allows us to ask the compount types themselves to apply the
coercion functions.  Almost all of the redundant logic that used to exist in
the `filter_by_role` functions is now in just the main implementation of
`apply_shape`.

Almost all of the tests are passing with this commit, except for two tests for
flattening behavior.  I am working on those next but feel this thought is now
complete and worth committing.
Added the `print_none` keyword to `apply_shape`.  This completes the migration
towards a recursive structure for the main serialization functions.

Also with this commit, every test is passing.  Wahoo!
Merge branch 'fix_recursion'
Merging in latest changes from the community.

Merge branch 'master' of github.com:j2labs/schematics
v0.9
Fixing version string
Fixing travis link in docs
My name was listed twice.
Adjusted `apply_shape` so that the role argument is now optional everywhere.
Removed unnecessary argument `shape_converter` from `apply_shape` loop.  Logic is cleaner now.
Adjusted functions in `schematics.serialize` to work on classes instead of instances.
Merge branch 'upstream/master'
Added comments and am starting the process of cleaning up the code.  No logical changes.
Adjusting the arrangement of functions
Moved all functions over to operating on classes.  I also wrote docstrings for the functions that did not already have them.
Wrote more documentation.  w00t!