Fix building with build.py on Windows (#3013)

Changes:
  - gen-doctest.py: Use slashes in paths to make cmake happy.
  - unit-doc/CMakeLists.txt: Don't add invalid arguments to MSVC and call gen-doctest.py properly.
  - build.py: Build and install with cmake calls on Windows.

JerryScript-DCO-1.0-Signed-off-by: Csaba Osztrogonác oszi@inf.u-szeged.hu

tools/gen-doctest.py

@@ -96,7 +96,7 @@ class DoctestExtractor(object):
         :param decl: the dictionary of the declaration parameters.
         :param code: the list of lines of the doctest.
         """
-        outname = os.path.join(self._outdir, decl['name'])
+        outname = os.path.join(self._outdir, decl['name']).replace('\\', '/')
         action = decl['test']
         if self._dry:
             print('%s %s' % (action, outname))