* Rename sch_item files to sch_junction.
* Make global variable g_ItemToRepeat a private member of SCH_EDIT_FRAME
object.
* Encapsulate SCH_SCREEN reference count member.
* Move schematic select block from global variable to SCH_EDIT_FRAME.
* Remove redundant schematic drawing code for eeredraw.cpp.
* Move block select code into SCH_SCREEN object.
* Simpilify block item select code.
* Fix bug in SCH_LINE selection state test.
* Add test to schematic objects for connectability.
* Make copy block items function a private method in SCH_EDIT_FRAME.
Eeschema: cleaning code. Start work to enhance annotation algorithm.
Already added an option to annotate using sheet number (sheet 1 uses numbers 100 to 199, sheet 2 uses 200 to 299..).
Works fine if deleting existing annotation, but needs work to be used when the existing annotation is kept .
Rename EDA_Rect::Inside to EDA_Rect::Contains ( EDA_Rect::Inside( const EDA_Rect& aRect ) was very ambiguous )
Fix some Doxygen warnings and erroneous comments; Add comments.