Feature/mbedtls (#84)

* try to import mbedtls and build it

* add stubs socket class

* some boilterplate, read and write function implemented

* more boilterplate / current error in handshake because no CA cert is setup

* add something so skip ca verification, can ws curl https://google.com !

* cleanup / close implemented

* tweak CMakefiles

* typo in include

* update readme

* disable unittests

.travis.yml

@@ -1,5 +1,8 @@
 language: bash
 
+# See https://github.com/amaiorano/vectrexy/blob/master/.travis.yml
+# for ideas on installing vcpkg
+
 matrix:
   include:
     # macOS