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.comp.pem

@@ -0,0 +1,6 @@
+-----BEGIN EC PRIVATE KEY-----
+MIGYAgEBBEA3LJd49p9ybLyj9KJo8WtNYX0QKA15pqApzVGHn+EBKTTf5TlUVTN9
+9pBtx9bS7qTbsgZcAij3Oz7XFkgOfXHSoAsGCSskAwMCCAEBDaFEA0IAAji37JK2
+HFxsf7wopOx1nUj81OLjdN79XElopU2+91EOUXiG+/w46jmqUpNZ1wpxVsNdPLrH
+zndr2yUd1kvOcSM=
+-----END EC PRIVATE KEY-----