move looksLikeLatLonPair into lib.php, basic PHP test suite using phpunit
update osm2pgsql (protobuf lib)

fixes #175
experimental tweaking of ranks of searches

- completely removes partial words with spaces from addresses
- ensure that frequent partial search terms appear in NonAddress
- higher penalty for partial words consisting of numbers
add finished message to setup.php
prepare next release
bump development version to 2.4
officially drop support for postgres 8.4
rewrite address interpolation so that planet_osm_node is not needed

This allows address interpolations to work correctly when flatnode storage
is used for node coordinates.

To fix interpolations in an existing database, follow these steps:

  * invalidate all interpolations (in psql):
    `UPDATE placex SET indexed_status=2 WHERE rank_search = 28`
  * disable updates:
    ./utils/setup.php --create-functions --create-partition-functions
  * reindex the whole lot:
    ./utils/update.php --index --index-instances <number of your cpus>
  * enable updates again:
    ./utils/setup.php --create-functions --enable-diff-updates --create-partition-functions
reintroduce index on gb_postcode
remove most landuses from addresses
respect bounded in country searches

fixes trac 5238
remove all unidentified large areas from addresses
adapt API tests to latest OSM data changes
PATH_INFO is delivered URL encoded on newer apache 2.4
fix typo in osm test file generator