These changes are added by carlopav in pull request #3102.
We add them in this commit already so that this branch and
that branch are easier to rebase and merge.
Small spacing fixes like imports in separate lines
for more clarity, and the position of the license.
Also use the new `messages` module to provide the functions
to print text to the console.
Many auxiliary tools used by `Draft.py` can be defined
in another module. Many functions are moved to this module
so that `Draft.py` isn't as big and hard to maintain.
The following is a list o functions that were moved:
`get3DView`, `autogroup`, `dimSymbol`, `dimDash`,
`removeHidden`, `formatObject`, `getSelection`,
`getSelectionEx`, `select`, `loadTexture`.
Moreover, many of these functions were renamed
to comply better with PEP8 guidelines,
particularly the use of `snake_case`. For example,
`get3DView` is now `get_3d_view`.
Aliases are provided for the old names so that
other functions and classes that depend on these
won't break. The new names should be the official
programming interface, while the old names
should be deprecated at some point in the future.
