Add support for replacing <line> and <column> with editor

[blueyed]

Issue type:

• Feature request

Version:

Vimperator: 3.14.0 (created: 2016/06/07 23:58:16)
Firefox:    Mozilla/5.0 (X11; Linux x86_64; rv:49.0) Gecko/20100101 Firefox/49.0

Description:

Please consider replacing <line> and <column> in the editor command.

This allows for using -c "call cursor(<line>, <column>)" with Vim, where the cursor will be placed where it was in the textarea or input field before.
This is supported by Pentadactyl, and therefore I suggest using the same names.