Require qt creator to locate the cmake project to build on non-windows

* Previously the cmake build would put librenderdoc.so in a /bin folder
  in the source folder so the qt creator project could link against a
  fixed path when just opening the project solo.
* This won't scale though for fetching the SWIG outputs from cmake, and
  it's ugly to modify the source folder for out-of-source builds.
* Instead we have cmake generate a qt creator include file with all of
  the settings and paths needed, and pass the CMAKE_BINARY_DIR into
  qmake when building. This does mean that when opening the project in
  qt creator you need to specify CMAKE_DIR=/path/to/build though.
* As a bonus, this means we can let cmake identify where python is and
  have qt creator link against it rather than having to hardcode include
  paths etc.

qrenderdoc/qrenderdoc.pro

@@ -68,10 +68,14 @@ win32 {
 	DEFINES += RENDERDOC_PLATFORM_WIN32
 
 } else {
-	isEmpty(DESTDIR) {
-		DESTDIR = $$_PRO_FILE_PWD_/../bin
+	isEmpty(CMAKE_DIR) {
+		error("When run from outside CMake, please set the Build Environment Variable CMAKE_DIR to point to your CMake build root. In Qt Creator add CMAKE_DIR=/path/to/renderdoc/build under 'Additional arguments' in the qmake Build Step. If running qmake directly, add CMAKE_DIR=/path/to/renderdoc/build/ to the command line.")
 	}
 
+	DESTDIR=$$CMAKE_DIR/bin
+
+	include($$CMAKE_DIR/qrenderdoc/qrenderdoc_cmake.pri)
+
 	# Temp files into .obj
 	MOC_DIR = .obj
 	UI_DIR = .obj
@@ -79,7 +83,7 @@ win32 {
 	OBJECTS_DIR = .obj
 
 	# Link against the core library
-	LIBS += -L$$DESTDIR -lrenderdoc
+	LIBS += -lrenderdoc
 	QMAKE_LFLAGS += '-Wl,-rpath,\'\$$ORIGIN\',-rpath,\'\$$ORIGIN/../lib\''
 
 	CONFIG += warn_off
@@ -91,7 +95,7 @@ win32 {
 		DEFINES += RENDERDOC_PLATFORM_POSIX RENDERDOC_PLATFORM_APPLE
 		ICON = $$OSX_ICONFILE
 
-		INFO_PLIST_PATH = $$shell_quote($${DESTDIR}/$${TARGET}.app/Contents/Info.plist)
+		INFO_PLIST_PATH = $$shell_quote($$DESTDIR/$${TARGET}.app/Contents/Info.plist)
 		QMAKE_POST_LINK += /usr/libexec/PlistBuddy -c \"Add :CFBundleShortVersionString string $${RENDERDOC_VERSION}.0\" -c \"Set :CFBundleIdentifier org.renderdoc.qrenderdoc\" $${INFO_PLIST_PATH}
 	} else {
 		QT += x11extras