Some major reworkings going on!

* reworked the api for the mesh part.
* remove the snode_t struct. didn't check to see if everything still
works. it probably doesn't.
* started writing a proper commandline argument hadnling
* moved the test functions to a special folder to make their use nicer
later on.
* created a tests folder for testing. already contains the amazing
minunit framework.
everything seems to work properly again. more testing is probably required
ok. good enough for me