translate: implement a counter to export the code line number
translate: implement a counter to export the code line number

Before this, all code sources were like "#: code:foo/bar.py:0", now
they will have line no like "#: code:foo/bar.py:123".

Note that the gettext() wouldn't be affected, since it doesn't consult
the file name or line so far.

xrg/openerp-server,xrg/openerp-server