Updates spdx.file.File docstring. Adds add_lics, add_contrib, add_depend and add_artificat methods to spdx.file.File class. Implements spdx.file.File validate method.
Updates spdx.file.File docstring.
Adds add_lics, add_contrib, add_depend and add_artificat methods to spdx.file.File class.
Implements spdx.file.File validate method.

Signed-off-by: Ahmed H. Ismail <17be99835f39b7679f83bf2695d44e1f53f60100@gmail.com>

spdx/tools-python,bmwcarit/spdx-tools-python,ah450/spdx-tools-python