Possible fix for :includes header argument in org-babel C source blocks

[Ori]

Hi Brandon,

Some other interesting test results, the first of which makes me think that 
string un-escaping could be going too far and perhaps the problem lies 
elsewhere:

    :includes "example.h\""
results in:
    #includes example.h"

    :includes '("\"/some/path/to/example.h\"" "<example_2.h>")
results in:
    #include "/some/path/to/example.h"
    #include <example_2.h>

That works with just one sting in the list as well:
    :includes '("\"/some/path/to/example.h\"")
results in:
    #include "/some/path/to/example.h"


This is on Emacs 26 with org 9.3.4

Ori