update cMake build documentation

Remove the dependency on libxml, no longer needed.

CMakeLists.txt

@@ -45,8 +45,6 @@ if (NOT ONLY_DOCS)
     endif()
     add_subdirectory(osm2pgsql)
 
-    find_package(Threads REQUIRED)
-
     unset(PostgreSQL_TYPE_INCLUDE_DIR CACHE)
     set(PostgreSQL_TYPE_INCLUDE_DIR "/usr/include/")
     find_package(PostgreSQL REQUIRED)
@@ -74,13 +72,6 @@ if (NOT ONLY_DOCS)
         message(FATAL_ERROR "Postgresql server package not found.")
     endif()
 
-    find_package(ZLIB REQUIRED)
-
-    find_package(BZip2 REQUIRED)
-
-    find_package(LibXml2 REQUIRED)
-    include_directories(${LIBXML2_INCLUDE_DIR})
-
     # Setting PHP binary variable as to command line (prevailing) or auto detect
     if (NOT PHP_BIN)
          find_program (PHP_BIN php)

docs/admin/Installation.md

@@ -25,24 +25,20 @@ and can't offer support.
 For compiling:
 
   * [cmake](https://cmake.org/)
-  * [libxml2](http://xmlsoft.org/)
+  * [expat](https://libexpat.github.io/)
+  * [proj](https://proj.org/)
+  * [bzip2](http://www.bzip.org/)
+  * [zlib](https://www.zlib.net/)
+  * [Boost libraries](https://www.boost.org/), including system and filesystem
+  * PostgreSQL client libraries
   * a recent C++ compiler (gcc 5+ or Clang 3.8+)
 
-Nominatim comes with its own version of osm2pgsql. See the
-[osm2pgsql README](https://github.com/openstreetmap/osm2pgsql/blob/master/README.md#building)
-for additional dependencies required for compiling osm2pgsql.
-
-For running tests:
-
-  * [behave](http://pythonhosted.org/behave/)
-  * [Psycopg2](https://initd.org/psycopg)
-  * [nose](https://nose.readthedocs.io)
-  * [phpunit](https://phpunit.de)
-
 For running Nominatim:
 
   * [PostgreSQL](https://www.postgresql.org) (9.3 or later)
   * [PostGIS](https://postgis.org) (2.2 or later)
+  * [Python 3](https://www.python.org/)
+  * [Psycopg2](https://initd.org/psycopg)
   * [PHP](https://php.net) (7.0 or later)
   * PHP-pgsql
   * PHP-intl (bundled with PHP)
@@ -52,6 +48,12 @@ For running continuous updates:
 
   * [pyosmium](https://osmcode.org/pyosmium/) (with Python 3)
 
+For running tests:
+
+  * [behave](http://pythonhosted.org/behave/)
+  * [nose](https://nose.readthedocs.io)
+  * [phpunit](https://phpunit.de)
+
 ### Hardware
 
 A minimum of 2GB of RAM is required or installation will fail. For a full

vagrant/Install-on-Centos-7.sh

@@ -32,7 +32,7 @@
                         wget git cmake make gcc gcc-c++ libtool policycoreutils-python \
                         devtoolset-7 llvm-toolset-7 \
                         php-pgsql php php-intl libpqxx-devel \
-                        proj-epsg bzip2-devel proj-devel libxml2-devel boost-devel \
+                        proj-epsg bzip2-devel proj-devel boost-devel \
                         expat-devel zlib-devel
 
 # If you want to run the test suite, you need to install the following

vagrant/Install-on-Ubuntu-16.sh

@@ -25,7 +25,7 @@ export DEBIAN_FRONTEND=noninteractive #DOCS:
 # Now you can install all packages needed for Nominatim:
 
     sudo apt-get install -y build-essential cmake g++ libboost-dev libboost-system-dev \
-                            libboost-filesystem-dev libexpat1-dev zlib1g-dev libxml2-dev\
+                            libboost-filesystem-dev libexpat1-dev zlib1g-dev\
                             libbz2-dev libpq-dev libproj-dev \
                             postgresql-server-dev-9.5 postgresql-9.5-postgis-2.2 \
                             postgresql-contrib-9.5 \

vagrant/Install-on-Ubuntu-18-nginx.sh

@@ -18,7 +18,7 @@ export DEBIAN_FRONTEND=noninteractive
 
     sudo apt-get update -qq
     sudo apt-get install -y build-essential cmake g++ libboost-dev libboost-system-dev \
-                            libboost-filesystem-dev libexpat1-dev zlib1g-dev libxml2-dev\
+                            libboost-filesystem-dev libexpat1-dev zlib1g-dev\
                             libbz2-dev libpq-dev libproj-dev \
                             postgresql-server-dev-10 postgresql-10-postgis-2.4 \
                             postgresql-contrib-10 \

vagrant/Install-on-Ubuntu-18.sh

@@ -25,7 +25,7 @@ export DEBIAN_FRONTEND=noninteractive #DOCS:
 # Now you can install all packages needed for Nominatim:
 
     sudo apt-get install -y build-essential cmake g++ libboost-dev libboost-system-dev \
-                            libboost-filesystem-dev libexpat1-dev zlib1g-dev libxml2-dev \
+                            libboost-filesystem-dev libexpat1-dev zlib1g-dev\
                             libbz2-dev libpq-dev libproj-dev \
                             postgresql-server-dev-10 postgresql-10-postgis-2.4 \
                             postgresql-contrib-10 postgresql-10-postgis-scripts \