added methods for creating stroke attributes

Signed-off-by: K <mustkre8@gmail.com>
now generating json file when running test

Signed-off-by: K <mustkre8@gmail.com>
add support for stroke color and width attributes

Signed-off-by: K <mustkre8@gmail.com>
updated readme and  screenshot

Signed-off-by: K <mustkre8@gmail.com>
Merge branch 'master' of github.com:iksnae/JSONAttributedString

Signed-off-by: K <mustkre8@gmail.com>

Conflicts:
	example.json