QueryPanel: allow case-insensitive string comparison WFS Filters

[justb4]

gxp.QueryPanel allows one to construct spatial and attribute filters interactively. Attribute Filters are constructed and encoded using OpenLayers' Filter, in particular OpenLayers.Filter.Comparison. This Filter, allows a config parameter 'matchCase', which, when set to 'false' will encode an OGC Filter attribute matchCase="true" in Comparison Filters like <ogc:PropertyIsEqualTo >. Think WFS needs to be 1.1.0 or higher. It will be very useful and trivial to add a configuration parameter to QueryPanel to allow matchCase to be specified. A step further would be to add a GUI widget, maybe via plugin, to specify matchCase interactively. But to add as a configuration parameter, with a more meaningful name such as 'caseInsensitiveMatch' is quite trivial and has been proven to work.

In QueryPanel.initComponent:

   this.filterBuilder = new gxp.FilterBuilder({
        //anchor: "-8px",
        attributes: this.attributeStore,
        allowGroups: false,
        caseInsensitiveMatch: this.caseInsensitiveMatch
    });

And use this in gxp.FilterBuilder (and gxp.form.FilterField to be on the safe side):

createDefaultFilter: function() {
    return new OpenLayers.Filter.Comparison({
                        matchCase: !this.caseInsensitiveMatch});
},

This results in matchCase="true" in Comparison Filters like ogc:PropertyIsEqualTo.

I have made these changes in my GXP clone and can issue a pull request. Let me know if found useful.

Same story may be for Wildcards, but need to dive into.

[ahocevar]

This looks good. Can you turn it into a pull request? Thanks.