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_384_prv.pem

@@ -0,0 +1,6 @@
+-----BEGIN EC PRIVATE KEY-----
+MIGkAgEBBDA/XY2b4oC1aWzFzJ+Uz4r35rYd1lkrKrKzpMYHRQQX7DJ9zcrtfBAF
+PXGaBXTwp2qgBwYFK4EEACKhZANiAATZxmK1C6KcpHmQRQ4EOur08MabFWdtES9i
+KnHJMFmvmZaRxWgNK0TREVedsS9KQTou1cRfz7Z7W2PgC5Hr5Z0JprGsLAxCgqoS
+MX7VkU+Zm8SIuxMug0LMNvLKXjN5x0c=
+-----END EC PRIVATE KEY-----