Feat/trailing chord test and tweaks

[isaiahdahl]

Added a test for the trailing chord.

While adding the test I noticed something that was a bit off so I made an adjustment.

before it would render like this:

Where the first chord lyric pair would create this block

Where it's a chord "D" paired up with a space.

The problem was that the space just doesn't have any impact on the formatting because the chord character would always be wider than the space. Though intuitively I would like to see a space character between the chord and the next lyric. Which you can also see in #214 PraiseCharts examples.

In this PR I adjusted the formatters so that when lyrics = ' ' it add's a space to the chord.

This makes it so that it looks like this:

This also creates a benefit for when there are chords in chordpro only separated by a space.

ie:

Let it [Am]be, let it [C/G]be, let it [F]be, let it [C]be
[C]Whisper words of [F]wis[G]dom, let it [F]be [C/E] [Dm] [C]

With this PR there will be a space rendered between the 3 chords at the end, Instead of being right next to each other.

Thoughts?