Revert "Added the ability to format each cell after all calculations had occured"

This reverts commit f6d8dbc77d44c8fb7d42f8984f30cb16d0689327.

Despite being a useful feature, this is preventing me from easily refactoring
the code. I'll probably be adding this back in the future.
Remove Jeweler and RDoc tasks, and use Bundler.
Do not monkey-patch String in the tests.
Split table_spec.rb into smaller files.
Add performance test for #4.
Fixed performance issue with large number of rows
Add test for :horizontal_padding
Update documentation.

* Remove examples that pass a block to Text::Table.new
* Downplay #to_table core extension
Remove Rakefile.
Minor cleanup
Move dependencies to the gemspec and add a description and license.
Simplify require statements.
Update changelog and give credit.
Bump version.