javascriptRRD Files

Change Log (v0.5.0 -> v0.6.0):

* Created RRDFilter_js.html (the RRDFilter documentation page, which was forgotten in last release) and linked it to the main documentation index.

* Added to RRDFilter.js, a new group of classes for a new Filter: 
   - RRDRRAFilterAvg class to create a new RRD with 'filtered' RRAs in the same manner as RRDFilterOp: A filter object containing a new step size and a base RRA are used to create a new RRA with that step size whose data is averaged from the base RRA.
   - RRAFilterAvg creates these new 'filtered' RRAs, 
   - RRAInfoFilterAvg creates their respective RRAInfo classes,
And RRDRRAFilterAvg links them all together into the RRD.

* Added to RRDFlot: rrdflot_defaults are passed into new Flot objects to set defaults. These defaults are set initially when the graph is changed, but can be changed by the user. The options that are now available are, in the same order as provided in the documentation:
    - legend location;
    - number of checkboxes per column;
    - an option to create a button above each column which selects all the buttons in that column;
    - an option to append the aggregation function name to a DS (data set/element) in the case of multiple DSs of the same name but different agg function;
    - an option to append the consolidateion function name to an RRA in the case of multiple RRAs with the same name but different CFs. 
    - an option to use a user-provided list of DSs to be checked initially
    - the list of checked DSs mentioned above
    - an option to use the RRA index specified below.
    - the RRA index mentioned above.
    - window zoom selection minimum
    - window zoom selection maximum
    - graph heigh
    - graph width
    - scale height, scale being the smaller graph below the main graph 
    - scale width
    - timezone.

* In RRDFlot.js, a timezone selection drop-down box was added to the flot graph, with ability to change the timezone built into the graph itself. 
* RRDFlotSupport.js has an argument added to one of it's helper functions to accommodate this timezone addition.

* Updated documentation and examples to reflect all of these changes.
* Added two new example pages (rrdJFlotDefaults.html and rrdJFlotFilterRRA.html) to highlight new changes.