Update OCI8 README

Author: cjbj

ext/oci8/README

@@ -11,14 +11,14 @@ 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 12, 11, or 10.2
+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
-http://www.oracle.com/technetwork/database/features/instant-client/
-Install the 'Basic' or 'Basic Lite' Instant Client package.  If
+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 connectivity 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
+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.