[m-rev.] for post-commit review: convert another README to Markdown

[Julien Fischer]

For possible post-commit review ...

-----------------------------------

Convert another README to Markdown.

samples/c_interface/README:
     Rename to README.md and convert the contents to Markdown.

Julien.

diff --git a/samples/c_interface/README b/samples/c_interface/README
deleted file mode 100644
index 68266a2ed..000000000
--- a/samples/c_interface/README
+++ /dev/null
@@ -1,30 +0,0 @@
-
-This directory contains some examples of mixed Mercury/C programs using
-the foreign language interface.
-
-short_example.m                 A short example of Mercury code calling C.
-
-mercury_calls_c                 A detailed example of Mercury code
-                                calling C code.
-
-c_calls_mercury                 A detailed example of C code calling
-                                Mercury code.
-
-mercury_calls_cplusplus         A detailed example of Mercury code
-                                calling C++ code.
-
-cplusplus_calls_mercury         A detailed example of C++ code calling
-                                Mercury code.
-
-mercury_calls_fortran           This directory contains a detailed
-                                example of Mercury code calling Fortran code.
-
-simpler_c_calls_mercury         A simpler example of C code calling Mercury.
-
-simpler_cplusplus_calls_mercury A simpler example of C++ code calling
-                                Mercury.
-
-standalone_c			Another example of C code calling Mercury
-				code this time use the compiler's 
-				`--generate-standalone-interface' option.
-
diff --git a/samples/c_interface/README.md b/samples/c_interface/README.md
new file mode 100644
index 000000000..16528f300
--- /dev/null
+++ b/samples/c_interface/README.md
@@ -0,0 +1,32 @@
+MERCURY C INTERFACE EXAMPLES
+============================
+
+This directory contains some examples of mixed Mercury/C/C++/Fortran programs
+using the foreign language interface.
+
+* [short_example.m](short_example.m) -- A short example of a Mercury code
+  calling C code.
+
+* [mercury_calls_c](mercury_calls_c) -- A detailed example of Mercury code
+  calling C code.
+
+* [c_calls_mercury](c_calls_mercury) -- A detailed example of C code calling
+  Mercury code.
+
+* [mercury_calls_cplusplus](mercury_calls_cplusplus) -- A detailed example of
+  Mercury code calling C++ code.
+
+* [cplusplus_calls_mercury](cplusplus_calls_mercury) -- A detailed example of
+  C++ code calling Mercury code.
+
+* [mercury_calls_fortran](mercury_calls_fortran) -- This directory contains a
+  detailed example of Mercury code calling Fortran code.
+
+* [simpler_c_calls_mercury](simpler_c_calls_mercury) -- A simpler example of C
+  code calling Mercury.
+
+* [simpler_cplusplus_calls_mercury](simpler_cplusplus_calls_mercury) -- A
+  simpler example of C++ code calling Mercury.
+
+* [standalone_c](standalone_c) -- Another example of C code calling Mercury
+  code this time using the compiler's `--generate-standalone-interface` option.