[ci skip] Migrate oci8 README to Markdown

Author: petk

ext/oci8/README

@@ -0,0 +1,23 @@
+# The OCI8 Extension
+
+Use the OCI8 extension to access Oracle Database.
+
+Documentation is at https://www.php.net/oci8
+
+Use `pecl install oci8` to install for PHP 7.
+
+Use `pecl install oci8-2.0.12` to install for PHP 5.2 - PHP 5.6.
+
+Use `pecl install oci8-1.4.10` to install for PHP 4.3.9 - PHP 5.1.
+
+The OCI8 extension needs to be linked with Oracle 18, 12, 11, or 10.2 client
+libraries. These libraries are found in your database installation, or in the
+free Oracle Instant Client from
+https://www.oracle.com/technetwork/database/database-technologies/instant-client/overview/index.html
+Install the 'Basic' or 'Basic Light' Instant Client package. If building from
+source, then also install the SDK package.
+
+Oracle's standard cross-version interoperability applies. For example, PHP OCI8
+linked with Instant Client 11.2 can connect to Oracle Database 9.2 onward. See
+Oracle's note "Oracle Client / Server Interoperability Support" (ID 207303.1)
+for details.

ext/oci8/README.md

@@ -461,7 +461,7 @@ Internal change: Convert some parameter parsing to the Fast Parameter Parsing AP
    <file name="oci8_failover.c" role="src" />
    <file name="php_oci8.h" role="src" />
    <file name="php_oci8_int.h" role="src" />
-   <file name="README" role="doc" />
+   <file name="README.md" role="doc" />
   </dir> <!-- / -->
  </contents>
  <dependencies>