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/dir-maxpath/04.key

@@ -0,0 +1,8 @@
+-----BEGIN EC PARAMETERS-----
+BggqhkjOPQMBBw==
+-----END EC PARAMETERS-----
+-----BEGIN EC PRIVATE KEY-----
+MHcCAQEEIDQvTm0wfEAKoymv8ePBv7cRxrnM4g6LREnSll5ghQsXoAoGCCqGSM49
+AwEHoUQDQgAEFFw4HFFTU/YaL22RORy+q4zm+wuecBLlik4VfwnGeK1q18e1Vx2H
+Q/0d2gwOyUr2KZtrE6JOIrG5Q84WTPxgzQ==
+-----END EC PRIVATE KEY-----