Remove unneeded swap() (thanks Jean-Marc)

std::swap() does exactly the same thing, and avoiding code duplication is
always good.

src/Length.cpp

@@ -57,13 +57,6 @@ Length::Length(string const & data)
 }
 
 
-void Length::swap(Length & rhs)
-{
-	std::swap(val_, rhs.val_);
-	std::swap(unit_, rhs.unit_);
-}
-
-
 string const Length::asString() const
 {
 	ostringstream os;

src/Length.h

@@ -67,8 +67,6 @@ public:
 	/// "data" must be a decimal number, followed by a unit
 	explicit Length(std::string const & data);
 
-	///
-	void swap(Length & rhs);
 	///
 	double value() const;
 	///

src/insets/InsetTabular.cpp

@@ -628,30 +628,6 @@ Tabular::CellData & Tabular::CellData::operator=(CellData const & cs)
 	return *this;
 }
 
-void Tabular::CellData::swap(CellData & rhs)
-{
-	std::swap(cellno, rhs.cellno);
-	std::swap(width, rhs.width);
-	std::swap(multicolumn, rhs.multicolumn);
-	std::swap(multirow, rhs.multirow);
-	std::swap(mroffset, rhs.mroffset);
-	std::swap(alignment, rhs.alignment);
-	std::swap(valignment, rhs.valignment);
-	std::swap(decimal_hoffset, rhs.decimal_hoffset);
-	std::swap(decimal_width, rhs.decimal_width);
-	std::swap(voffset, rhs.voffset);
-	std::swap(top_line, rhs.top_line);
-	std::swap(bottom_line, rhs.bottom_line);
-	std::swap(left_line, rhs.left_line);
-	std::swap(right_line, rhs.right_line);
-	std::swap(usebox, rhs.usebox);
-	std::swap(rotate, rhs.rotate);
-	std::swap(align_special, rhs.align_special);
-	p_width.swap(rhs.p_width);
-	inset.swap(rhs.inset);
-}
-
-
 Tabular::RowData::RowData()
 	: ascent(0),
 	  descent(0),

src/insets/InsetTabular.h

@@ -612,8 +612,6 @@ public:
 		///
 		CellData & operator=(CellData const &);
 		///
-		void swap(CellData & rhs);
-		///
 		idx_type cellno;
 		///
 		int width;