Count individual testcases when running tests.

The idea is simple: each print represents a testcase within a test unit.
As we don't have strict rules on which/how many testcase are put into
a test file, it's nice to have an idea how many *testcases* we have
totally. Would be nice to count how many testcases pass/fail, but
that's a bit less trivial.
Implement str.strip
Improved type/class/instance code; mp_obj_type_t now has load_attr, store_attr.

Creating of classes (types) and instances is much more like CPython now.
You can use "type('name', (), {...})" to create classes.
py: Implement base class lookup, issubclass, isinstance.
Merge pull request #121 from pfalcon/count-testcases

Count individual testcases when running tests.
Merge pull request #123 from xbe/master

Implement str.strip
Merge pull request #127 from iabdalkader/master

Add USART Micro Python Bindings
Use memcpy instead of strncpy; add usart.status to stm.