Adding the ability to rename columns

...And keep the data in them.
Use the adapter to quote the value.
Merge remote-tracking branch 'upstream/master' into rename-column

Conflicts:
	lib/lhm/chunker.rb
	spec/integration/lhm_spec.rb
DRY up sourcing the config file in preparation for making more changes
These scripts are all written against /bin/sh. If /bin/sh is strict Bourne shell, the ~ construct does not work.
Add the LHM_TEST_CONFIG environment variable to allow the configuration file to live somewhere other than the user home directory
The master port should not be hardcoded in the grants setup
Ensure that single record tables are correctly copied.

This is a rare corner case, but it was sending me down the rabbit hole in spec testing.
qualified table names should also be quoted to allow reserved words
Merge branch 'single-row-tables' into rename-column
Merge pull request #39 from erikogan/rename-column

Adding the ability to rename columns
Add documentation about throttlers
Merge pull request #80 from phacops/update-documentation-throttler

Add documentation about throttlers
Include renames when instantiating
Merge pull request #82 from orien/fix_build

Fix the build
Add support for tables with outbound foreign key constraints.

Brute force the new constraint names by offsetting the (optional) index in the name by the total number of keys.
A much better way to ensure constraint name uniqueness

Reads all of the constraint names and makes sure to choose one that does not clash.
Actually test that the foreign key constraint is still there, rather than just dropped.
table constraints should only be foreign key constraints, since unique constraints are already stored in indices
Hash#slice is an ActiveSupport extension.

Do not assume it is present.
Fix tests