Character styles can be applied to individual chunk of text.
The function is creating a chunk of text associated with formatting
defined by several arguments.
font color - a single character value specifying
a valid color (e.g. "#000000" or "black").
size
font size (in point) - 0 or positive integer value.
bold
is bold
italic
is italic
underlined
is underlined
font
single character value specifying font name.
valign
single character value specifying font vertical alignments.
Expected value is one of the following : default 'baseline'
or 'subscript' or 'superscript'
shading
shading color - a single character value specifying
a valid color (e.g. "#000000" or "black").