title: error "missing separator" in build qwt-6.1
body: <p>My environment:</p>
  
  <pre><code>QT: Qt_5_0_2
  QWT: qwt-6.1-rc3
  MinGW: mingw47_32
  OS: win7_32
  </code></pre>
  
  <p>I follow the introduction file "INSTALL"'s step:</p>
  
  <pre><code>C) Win32/MinGW 
  Check that your Qt version has been built with MinGW - not with MSVC !
  
  Start a Shell, where Qt4 is initialized. ( F.e. with
  "Programs-&gt;Qt by Trolltech ...-&gt;Qt 4.x.x Command Prompt" ).
  Check if you can execute "make" or something like "mingw32-make".
  
  qmake qwt.pro
  make
  make install
  </code></pre>
  
  <p>I get the error in the step "make":</p>
  
  <pre><code>C:\qwt-6.1-rc3&gt;qmake qwt.pro
  
  C:\qwt-6.1-rc3&gt;mingw32-make
  cd src\ &amp;&amp; ( if not exist Makefile E:\Qt\5.0.2\5.0.2\mingw47_32\bin\qmake.exe C:
  \qwt-6.1-rc3\src\src.pro -o Makefile ) &amp;&amp; mingw32-make -f Makefile
  mingw32-make[1]: Entering directory 'C:/qwt-6.1-rc3/src'
  mingw32-make -f Makefile.Release all
  mingw32-make[2]: Entering directory 'C:/qwt-6.1-rc3/src'
  Makefile.Release:305: *** missing separator.  Stop.
  mingw32-make[2]: Leaving directory 'C:/qwt-6.1-rc3/src'
  Makefile:40: recipe for target 'release-all' failed
  mingw32-make[1]: *** [release-all] Error 2
  mingw32-make[1]: Leaving directory 'C:/qwt-6.1-rc3/src'
  makefile:44: recipe for target 'sub-src-make_first-ordered' failed
  mingw32-make: *** [sub-src-make_first-ordered] Error 2
  </code></pre>
  
  <p>The lines <strong>304,305</strong> in "Makefile.Release" are:</p>
  
  <pre><code>304 qmake:  FORCE
  305     @$(QMAKE) -o Makefile.Release src.pro
  </code></pre>
  
  <p>Where is wrong?</p>
  
  <p>thanks</p>