Store page numbers in Page classes

Although the document class keeps the page number, the sub pages may
need to know the page number as well. For example X/27 packets
contain relative magazine numbers which need the current page number
to calculate the actual page numbers referenced.

pagebase.cpp

@@ -23,6 +23,7 @@
 
 PageBase::PageBase()
 {
+	m_pageNumber = 0x8ff;
 	m_pageFunction = PFLOP;
 	m_packetCoding = PC7bit;
 	// We use nullptrs to keep track of allocated packets, so initialise them this way
@@ -34,6 +35,7 @@ PageBase::PageBase()
 
 PageBase::PageBase(const PageBase &other)
 {
+	setPageNumber(other.pageNumber());
 	setPageFunction(other.pageFunction());
 	setPacketCoding(other.packetCoding());
 	for (int i=0; i<8; i++)
@@ -50,6 +52,11 @@ PageBase::~PageBase()
 			delete m_packets[i];
 }
 
+void PageBase::setPageNumber(int newPageNumber)
+{
+	m_pageNumber = newPageNumber;
+}
+
 QByteArray PageBase::packet(int packetNumber, int designationCode) const
 {
 	int arrayIndex = packetNumber;