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_prv.pk8.pw.pem

@@ -0,0 +1,6 @@
+-----BEGIN ENCRYPTED PRIVATE KEY-----
+MIGRMBwGCiqGSIb3DQEMAQEwDgQIIrlmCCSpJzcCAggABHGm2LyJ60ojfilRRp8h
+Xf+sWL3lJq6wlj4Nk41SHVnZ2RiVtP5NVK908/WxnXkridd6Qpjnq/14woWVmQxT
+IzhKFVi22YmQyBsNj+bEGDAE4c9qaby8u6zbzs7Qj29F90f/PiYsaIEGcNn/W88e
+XarNDw==
+-----END ENCRYPTED PRIVATE KEY-----