Added xcoll linetools and element classes to Line.

[freddieknets]

Description

Verify simple PR to expose some of the Xcoll API to the Line.

Checklist

Mandatory:

• [ ] I have added tests to cover my changes
• [ ] All the tests are passing, including my new ones
• [ ] I described my changes in this PR description

Optional:

• [ ] The code I wrote follows good style practices (see PEP 8 and PEP 20).
• [ ] I have updated the docs in relation to my changes, if applicable
• [ ] I have tested also GPU contexts