Use a workitems mapping file during export to convert work items ids

Introducing of `--export-work-item-mapping=` option to specify file path
How to migrate to TFS2013(Git) keeping work items association
Update Next.md
Add -I option to automatically find the remote to use

Looking in the git history, we can easily find the tfs remote we must interact with.
Using this `-I` option (instead specifying the remote name with `-i`) permit
 to automatically find the good remote and use it...
'rcheckin --quick' should rebase local commits when fetching more than 1 changeset fetched
fix spaces
rcheckin : correct fail to checkin if changeset has been fetched

Take into account newly fetched changesets by updating parentChangeset variable
reset-remote : add a '--force' option when current commit does not belong to a remote or to the good one
update reset-remote doc
Reword.
Merge pull request #503 from pmiossec/reset_remote_force_option

reset-remote : add a '--force' option when current commit does not belon...
Merge pull request #501 from pmiossec/improve_rcheckin_quick

'rcheckin --quick' adjustements
Update Next.md
Update Next.md
update doc on `-I` option
work items association
Merge pull request #506 from pmiossec/Next.md

doc
Merge remote-tracking branch 'origin/master' into p504

Conflicts:
	doc/release-notes/NEXT.md
Merge pull request #504.
Merge remote-tracking branch 'origin/master' into p498

Conflicts:
	doc/release-notes/NEXT.md