Fixes to ProcessHelper

[Hecatron]

I spotted the problem listed here recently when trying to run QtSharp.CLI https://bugreports.qt.io/browse/QTBUG-55951

I noticed that the ProcessHelper class seems to hang on process.WaitForExit() when there's a problem with the called process (this has something to do with the redirection of stdout / stderr)

so I made a change to it to fix that also the output from stdout / stderr should now be visible on the console to see what's going on

Note process.WaitForExit(); is called regardless of the state of the waitForExit parameter since otherwise there's not enough time to get the standard output / standard error result for calls that need this result.

[Hecatron]

I think I've now covered all the changes you've mentioned I have run QtSharp.CLI and it seems to be all okay

A couple of things I've spotted, but I'm sure these aren't related to this change

• First some brackets needed to be added to init within QT_OPENGL_DECLARE within C:\Qt\Qt5.7.0\5.7\mingw53_32\include\QtGui\qopenglversionfunctions.h I think you already know about that one since I spotted the bug you raised for it

  private: \
  void init() {};

• Next about 3 of the inlines seem to fail to build Qt3DExtras-inlines.dll Qt3DQuickExtras-inlines.dll Qt3DRender-inlines.dll

I think this is just something specific to the version of Qt (I'm using 5.7.0)

[ddobrev]

The inlines of Qt3DRender are problematic too - https://bugreports.qt.io/browse/QTBUG-55952 . About the rest, I haven't had problems with them, I would guess they depend on Qt3DRender and this is why you have problems.