Set opacity to 1 if none passed to fillColor and strokeColor
Save the fill color and restore it after the line wrapper makes a new page
Fix indent
Fix textWidth
Add continued option to text so that text with inline styles can be created. Closes #60, #180, #189.

The following example adds text with three sections (part1, part2, part3) in different fonts and colors.

doc.font('Helvetica', 13)
   .text(part1, 100, 300, { continued: yes, indent: 50 })
   .fillColor('red')
   .text(part2, { indent: 50, continued: yes })
   .font('Times', 13)
   .fillColor('green')
   .text(part3)