in bezier_curves: changed  calculations like dx*dx to (double)dx * dx to avoid integer overflow in calculation

(all test are now always performed)

* Added modified version of FindwxWidgets.cmake to prevent manifest build and link errors
  with VC8.
* Fixed ambiguous math function ( sqrt, atan, cos, etc. ) call errors when building
  with MSVC.
* Moved bitmap copy bitmap source file destination to the build path to prevent source
  tree pollution and library rebuilds when building on different platforms.

Pcbnew: fixed a recent bug that could be creates errors in rats nest calculations (forgotten rats nets)

Pcbnew: fixed a recent bug that could be creates errors in rats nest calculations (forgotten rats nets)

Useful in compact designs to know hos to place a via during track creation.

Eeschema: code cleaning

some cleanup.

Solved a minor bug in Search in lib command when attempt to search a component name in non loaded libraries