Don't require webmock on boot

Otherwise we won't be able to make any requests in Rails :-)
Move Ogr classes to Ogr namespace
Remove feature count verification from cartodb importer

Ideally we won't need this at all, and we can return it if we come
across any problems
Tests for CartoDB Importer
Shapefile "model" returns list of column names
Namespace shapefile splitter
Rename CartoDB importer to "Uploader"

This is slightly more representative of what we are doing here. While we
are definitely importing to cartodb, we are really just using the import
api as a tool to upload to CartoDB so that we can hack around with and
merge our split up shapefiles. The uploader and merger will be handled
by a parent import class, which I think is more aptly named.
Make Ogr::Shapefile more generic, with no dependency on ShapefileMake
Ogr::Shapefile more generic, with no dependency on Shapefile
Move Shapefile split to Ogr split as it doesn't really have anything to
do with the Shapefile model
Correct name for Ogr:Split test
Correct name for CartoDb::Uploader test
Correct syntax for sql select in merger