To add a shortcut to end a line with separators [: ; , .] use these steps:

1. Tools -> Record Macro (Ctrl+Q).

2. Press End in a line and type a separator.

3. Tools -> Stop Recording Macro (Ctrl+Q).

4. Tools -> Save Macro.

5. Preferences  -> Key Bindings -> User.

6. Add the line

{"keys": ["<shortcut>"], "command": "run_macro_file", "args": {"file": "Packages/User/<macro-name>.sublime-macro"}}

End line with semicolon macro (end-semicolon.sublime-macro)

[
  {
    "args":
    {
      "extend": false,
      "to": "eol"
    },
    "command": "move_to"
  },
  {
    "args":
    {
      "characters": ";"
    },
    "command": "insert"
  }
]

The keyboard shortcut

{"keys": ["ctrl+;"], "command": "run_macro_file", "args": {"file": "Packages/User/end-semicolon.sublime-macro"}},