Reword readme for deployment with apache

Instructions based on cgimap.rb from chef. The instructions do not cover the apache configuration, just the cgimap part.

Also remove outdated references to since-renamed variables.
Add deployment instructions using cgimap.conf
Use LEFT JOIN instead of NOT IN subselect for ways_from_nodes
Rewrite apidb nodes_from_way_nodes completely
Rewrite apidb writable relations_from_ways
Rewrite apidb writable relations_from_nodes
Rewrite apidb writable relations_from_relations
Factor out subselect from add_nodes_list
Factor out subselect from add_ways_list
Factor out subselect from add_relations_list
Factor out subselect from nodes_from_relations
Merge pull request #64 from pnorman/readme_rewrite

Reword readme for deployment with apache
Factor out subselect from ways_from_relations
Factor out subselect from relation_members_of_relations
Add identifying information to header.

Adds the process ID and hostname to the generator string, which
allows pinpointing a single instance if it's misbehaving.
Merge pull request #69 from pnorman/left_join_subselect

Change subselects to left joins