Merge pull request #1582 from mtmail/documentation-direct-link-osm2pgsql

add wiki link to osm2psql README

diff --combined docs/admin/Installation.md
index b5176617d9c59c0720b2fd243a8d2f505aeb74d9,88a58b9100dedb28aa9b9f9348ef8457f8a7deec..2ed8ca7f4422f6938de00338b74bb78f614973d9
--- 1/docs/admin/Installation.md
--- 2/docs/admin/Installation.md
+++ b/docs/admin/Installation.md
@@@ -29,7 -29,8 +29,8 @@@ For compiling
    * a recent C++ compiler
  
  Nominatim comes with its own version of osm2pgsql. See the
- osm2pgsql README for additional dependencies required for compiling osm2pgsql.
+ [osm2pgsql README](https://github.com/openstreetmap/osm2pgsql/blob/master/README.md#building)
+ for additional dependencies required for compiling osm2pgsql.
  
  For running tests:
  
@@@ -45,6 -46,7 +46,6 @@@ For running Nominatim
    * [PHP](https://php.net) (7.0 or later)
    * PHP-pgsql
    * PHP-intl (bundled with PHP)
 -  * [PEAR::DB](https://pear.php.net/package/DB)
    * a webserver (apache or nginx are recommended)
  
  For running continuous updates: