Fix  #656 add font_size in create_captcha()
 Closing #656 and updating documentation

Signed-off-by: Preetham <me@preetham.in>
Removing extra spaces.

Signed-off-by: Preetham <me@preetham.in>
Updating changelog.rst for #656

Signed-off-by: Preetham <me@preetham.in>
removed additional tabs and semicolon

Signed-off-by: Preetham <me@preetham.in>
Merge pull request #3325 from preems/develop

closing  #656 add font_size in create_captcha()