fix titlecase fixes #4 @hijonathan @b-ash

  - also added capitalizeAll for old behavior
version bump for titlecase and capitalizeAll
update docs and add one more test
documentation update
standardize heading sizes
more descriptive describe
update install instructions
fix titlecase fixes #4 @hijonathan @b-ash

  - also added capitalizeAll for old behavior

  - version bump for titlecase and capitalizeAll

  - documentation update
Merge branch 'titlecase' of github.com:HubSpot/humanize into titlecase