NULL _all_ unset values when resizing during push

This prevents reinit from crashing.
Always calculate the new top after pushing

This way we don't end up in no mans' land when calling teh deinit
callback.
Fix transaction deinitialization

We shall not deinitialize uninitialized parts of an array!!!11eleven
Add an empty config file to be found by waysome on startup

The configuration file may be expanded later.
Merge pull request #337 from neithernut/add-default-config

Add an empty config file to be found by waysome on startup
Merge pull request #336 from neithernut/fix-action_processor

Fix action processor
Fix the stack top fetching in ws_processor_prepare_args()

This patch fixes the stack top fetching in the
ws_processor_prepare_args() function. The problem was that the pushing
to the stack changes the stack and _realloc()_s it, if required. That
causes the stack object to be located in another position, which caused
everything to fail.

Suggested-by: Julian Ganz <julian.ganz@hs-furtwangen.de>
Add string test files
Add string test for initialization
Add test for checking empty string length
Add test for catting empty strings and checking their length afterwards
Add preparation for empty multicat string test
Add test for empty duplication of string objects
Add test for empty string cmp()
Add test for getting empty string as raw
Add test for setting string from literal
Add test for setting string from buffer on heap
Add setup/teardown functions for more complex string testing
Add string ncmp test
Add substr testing