1. Fixed issue with the testsuite failing when the shell is enabled.
2. Added option to echoserver to force the echo behavior instead of
the shell when shell is enabled.
1. Add an automated test suite.
2. Refactor the existing test and example code to be better components for the test suite.
3. Rename some of the internal functions used by the examples and test suite.
4. Echoserver now only handles one connection at a time, has option to exit after single connection.
5. Echoserver can do the port zero trick for the test suite.
6. Some whitespace changes.
7. Added a `(void)` to a variable to hush an unused assignment warning.