fixed broken links with ids > 1000 at less with non US locales

e.g. links like "lines.php?action=edit&line_id=1,817" are generated but
result into an error, flourish not being able to retrieve database
record 1817 from "1,817" string, at less in some cases where the server
is running using french locale

this patch make all links look like "lines.php?action=edit&line_id=1817"
whatever the locale is
fixed a bug introduced by previous commit

When the user wants to create a new Dashboard, this new one has not yet an id.
In the 'Dashboard::makeURL' function, the previously commited correction
throw an exception because the constructor of fNumber doesn't accept
empty argument.
A test is added to see if the id is empty.
Add custom arg to the dashboard from a web-browser

- get all the arguments of the request
- ignore the values defined in a list
- add or replace the value in the auto-generated url
	of the graph (Graph::drawGraph)
Add classical values of "from" on the dashboard

These values can be edited in the array defined in "dashboard.php"
If the user add custom options in the request, they aren't lost
Add functions : cloneGraph and cloneLine

This patch add the possibility of cloning a line in a graph
or cloning a graph in a dashboard.
bugfix: urls on top links setting from= didn't tolerate reverse-proxy

now, they do
Drawgraph: when no alias, only put the target

If the user hasn't set an alias for a line, the function Graph::DrawGraph
doesn't alias the target so that the user can set regular expression
in order to draw multiple lines
more reverse-proxy-friendly urls

many links used to begin with / which was uneasy to expose through a
reverse proxy
removing unique index on lines(graph_id,alias)

otherwise there could be only one line without alias per graph

to update an existing database, one should use this query:
  alter table eagle_tattle.lines drop index graph_id;
processor: config parameter to use a distinct graphite url within batch
Patch for the fix of broken links with id > 1000

The function "prepareXXXId" has been replaced by the "getXXXId" one
so that we doesn't need to instantiate a fNumber object
Merge pull request #42 from g76r/c4

dashboard fixes and enhancement