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/crl_expired.pem

@@ -0,0 +1,11 @@
+-----BEGIN X509 CRL-----
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+UG9sYXJTU0wxGTAXBgNVBAMTEFBvbGFyU1NMIFRlc3QgQ0EXDTExMDIyMDEwMjQx
+OVoXDTExMDIyMDExMjQxOVowKDASAgEBFw0xMTAyMTIxNDQ0MDdaMBICAQMXDTEx
+MDIxMjE0NDQwN1owDQYJKoZIhvcNAQEFBQADggEBAKgP1XmCIPbfY1/UO+SVFQir
+jArZ94QnQdoan4tJ29d8DmTxJ+z9/KyWNoGeOwc9P/2GQQaZahQOBr0f6lYd67Ct
+wFVh/Q2zF8FgRcrQV7u/vJM33Q2yEsQkMGlM7rE5lC972vUKWu/NKq8bN9W/tWxZ
+SFbvTXpv024aI0IRudpOCALnIy8SFhVb2/52IN2uR6qrFizDexMEdSckgpHuJzGS
+IiANhIMn5LdQYJFjPgBzQU12tDdgzcpxtGhT10y4uQre+UbSjw+iVyml3issw59k
+OSmkWFb06LamRC215JAMok3YQO5RnxCR8EjqPcJr+7+O9a1O1++yiaitg4bUjEA=
+-----END X509 CRL-----