Allow the progress bar to be incremented

Added an advance() method to increment the progress bar by an optional amount
Created a test for the new advance() method
Fixed the progress bar width calculation

This was previously hard-coded at a width of 80 characters,
which would cause tests to fail when they were run on wider terminals
Allow content to be output without a trailing newline character

Added a new inline() method which will not append a new line to the content
Created a test for the new inline() method
Merge pull request #23 from duncan3dc/output-without-newline

Allow content to be output without a trailing newline character
minor cleanup
Merge pull request #22 from duncan3dc/progress-bar-test-width

Fixed the progress bar width calculation
Merge pull request #21 from duncan3dc/progress-bar-advance

Addition of advance method for progress bar
no need to set the initial value for current, its already set at definition
updated logo location
allow for associative columns