Improve README file

Added installation instructions and useful links for the PHP OCI8 extension.

Author: sharadraju

README.md

@@ -2,7 +2,11 @@
 
 Use the PHP OCI8 extension to access Oracle Database.
 
-Documentation is at https://www.php.net/oci8
+Documentation is at https://www.php.net/oci8.
+
+Installation
+--------------------
+The PHP OCI8 extension is available in the PECL repository [here](https://pecl.php.net/package/oci8).
 
 Use `pecl install oci8` to install for PHP 8.2 and PHP 8.3.
 
@@ -20,9 +24,14 @@ PHP_DTRACE=yes before running `pecl install oci8`. For example, on Linux:
 You may additionally need the dtrace-devel or systemtap-sdt-devel package
 installed.
 
-The PHP OCI8 extension can be linked with Oracle client libraries from Oracle
+On Windows, pre-compiled OCI8 DLLs are available for download and quick use from
+the [PECL repository](https://pecl.php.net/package/oci8). You may use the DLL directly
+by including them in the `php.ini` file.
+See [OCI8 installation](https://www.php.net/manual/en/oci8.installation.php) for more details.
+
+The PHP OCI8 extension can be linked with Oracle Client libraries from Oracle
 Database 11.2 or later. These libraries are found in your database
-installation, or in the free Oracle Instant Client from
+installation, or in the free Oracle Instant Client packages from
 
   https://www.oracle.com/database/technologies/instant-client.html
 
@@ -34,6 +43,9 @@ OCI8 linked with Instant Client 19c can connect to Oracle Database 11.2 or
 later. See Oracle Support's note "Oracle Client / Server Interoperability
 Support" (ID 207303.1) for details.
 
+Useful Links
+------------
+
 A sample configuration php.ini file is at
   https://github.com/php/pecl-database-oci8/blob/main/oci8.ini