The Text Pastry plugin does the job very well. It offers the Insert Numbers Syntax.
Select multiple lines with CMD+SHIFT+L (Sublime default):
text|
text|
text|
text|
Move the cursor where you want it:
| text
| text
| text
| text
And insert numbers with Text Pastry by hitting CMD+ALT+N and entering 1 space 1 space 0:
1| text
2| text
3| text
4| text
Where 1 space 1 space 0 stands for:
- Integer to start with 1
- Increment by 1
- Padd leading zeros 0
Replace CMD with CTRL on Windows or Linux machines.