Support for PC platform (#12)

* improvements for cross-platform compiling

* moved tactility-core to libs/

* splitup improvements

* remove git/gitmodules from freertos

* better platformbetter platform checks

* added build scripts

* delete mbedtls

* re-add mbedtls

* fixes and improvements

* added pc build

* simplify build scripts

* revert build scrpit

* updated builds

* fix for pc

* fix for pc

* fix for build

libs/mbedtls/tests/data_files/ec_bp512_prv.pem

@@ -0,0 +1,7 @@
+-----BEGIN EC PRIVATE KEY-----
+MIHaAgEBBEA3LJd49p9ybLyj9KJo8WtNYX0QKA15pqApzVGHn+EBKTTf5TlUVTN9
+9pBtx9bS7qTbsgZcAij3Oz7XFkgOfXHSoAsGCSskAwMCCAEBDaGBhQOBggAEOLfs
+krYcXGx/vCik7HWdSPzU4uN03v1cSWilTb73UQ5ReIb7/DjqOapSk1nXCnFWw108
+usfOd2vbJR3WS85xI0Qk7nBJ7tBy8NvE15mW4XXVV+JjdjrpcJXAgec+fbLjitw9
+TJoEh7Ht6HbcH8phyQLpodhyK4YSko8YokhFWRo=
+-----END EC PRIVATE KEY-----