#41; Changed variadic parameters to array of arrays (this is because …

…variadic parameters cannot be passed down to other functions, and was needed to implement param with default value at protocol level).

Changed parameters with default value to overload with protocol extension, needed to use protocol when changing implementation of generator..
first draft for ExcelStatsReportFromDateGenerator. Now need to modify both generator to do the complete job from generating the report and the file to attach (HTML -> PDF or Excel).
few options:
1- keep the HTML to PDF conversion outside the report generator (the conversion need UI which seems to be incompatible with UnitTesting)
2- use call back instead of returning a string (allow for any intermediate process)
3- remove the HTML and HTML to PDF processes since that might not be necessary anymore once we can generate and attach an Excel file.
(or a combo of few above options)

Core Classes/HtmlStatsReportFromDate.swift

@@ -26,8 +26,12 @@ struct ReportCell
 
 enum VAlign: String { case bottom, top, middle }
 
-protocol StatsReportFromDate
+protocol StatsReportFromDateGenerator
 {
+    var startDate : Date { get }
+    var endDate : Date { get }
+    var siteSpecific : Bool { get }
+
     init(_ startDate: Date, toDate endDate: Date, _ siteSpecific: Bool)
 
     func addTitle(_ title : String)
@@ -36,17 +40,36 @@ protocol StatsReportFromDate
     func addLineOfInfoText(_ info : String)
     func addLineOfText(_ text : String)
     func addText(_ text : String)
-
-    func startTable(_ columnsSet : [ReportColumn]..., withAlternatingRowColor : Bool, withInformationText : String?)
+
+    func startTable(_ columnsSet : [[ReportColumn]])
+    func startTable(_ columnsSet : [[ReportColumn]], withAlternatingRowColor : Bool)
+    func startTable(_ columnsSet : [[ReportColumn]], withAlternatingRowColor : Bool, withInformationText : String?)
     func addTableRow(_ cells : [ReportCell])
     func addTotalRow(_ cells : [ReportCell])
     func endTable()
 
     func result() -> String
 }
 
+extension StatsReportFromDateGenerator
+{
+//    init(_ startDate: Date, toDate endDate: Date, _ siteSpecific: Bool = false)
+//    {
+//        self(startDate, endDate, siteSpecific)
+//    }
+
+    func startTable(_ columnsSet : [[ReportColumn]])
+    {
+        self.startTable(columnsSet, withAlternatingRowColor: false, withInformationText: nil)
+    }
+
+    func startTable(_ columnsSet : [[ReportColumn]], withAlternatingRowColor : Bool)
+    {
+        self.startTable(columnsSet, withAlternatingRowColor: withAlternatingRowColor, withInformationText: nil)
+    }
+}
 
-class HtmlStatsReportFromDate: StatsReportFromDate
+class HtmlStatsReportFromDate: StatsReportFromDateGenerator
 {
     let BG_ALTERNATECOLOR = "#E3E3E3"
     let BG_FILLEDCELL = "#000000"
@@ -99,7 +122,7 @@ class HtmlStatsReportFromDate: StatsReportFromDate
         report += text
     }
 
-    func startTable(_ columnsSet : [ReportColumn]..., withAlternatingRowColor : Bool = false, withInformationText : String? = nil)
+    func startTable(_ columnsSet : [[ReportColumn]], withAlternatingRowColor : Bool, withInformationText : String?)
     {
         isAlternatingRowColor = withAlternatingRowColor
         isGray = false
@@ -205,7 +228,7 @@ class HtmlStatsReportFromDate: StatsReportFromDate
     }
 }
 
-class ExcelStatsReportFromDate: StatsReportFromDate
+class ExcelStatsReportFromDate: StatsReportFromDateGenerator
 {
     let BG_ALTERNATECOLOR = "#E3E3E3"
     let BG_FILLEDCELL = "#000000"
@@ -271,7 +294,7 @@ class ExcelStatsReportFromDate: StatsReportFromDate
         rowsOnCurrentSheet.append(ExcelRow(cells))
     }
 
-    func startTable(_ columnsSet: [ReportColumn]..., withAlternatingRowColor: Bool, withInformationText: String? = nil)
+    func startTable(_ columnsSet: [[ReportColumn]], withAlternatingRowColor: Bool, withInformationText: String?)
     {
         isAlternatingRowColor = withAlternatingRowColor
         isGray = false