Allow removing "start" and "end" from line labels

[jidanni]

Regarding side panel > Top level > ... > Routes > Properties > Drawing > Draw Name >

• start only
• end only

etc. Please have a checkbox, (in the checked state, for backwards compatibility):

• [x] include the words "start" and "end" in the label.

Else the user has no way to remove them if unwanted. E.g., they just want

Nerd St. Nerd St. Nerd St.

not

Nerd St. start Nerd St. Nerd St. end

Also regarding the center labels,

-----A-----
 -----B-----
-----C-----

it would be great to have an additional way to make them all line up, even if their details are slightly different.