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_pub.comp.pem

@@ -0,0 +1,4 @@
+-----BEGIN PUBLIC KEY-----
+MFowFAYHKoZIzj0CAQYJKyQDAwIIAQENA0IAAji37JK2HFxsf7wopOx1nUj81OLj
+dN79XElopU2+91EOUXiG+/w46jmqUpNZ1wpxVsNdPLrHzndr2yUd1kvOcSM=
+-----END PUBLIC KEY-----