Fixed bug 4758 - hgignore clion build artifacts

Malte

clion builds into cmake-build-debug, cmake-build-release etc. by default. Also, it creates the .idea forlder in wich it places some (mostly local) config.

Since SDL is perfectly buildable from within the IDE, i think it'd be nice to have the build and ide artifacts ignored by hg.

.hgignore

@@ -11,6 +11,10 @@ build
 gen
 Build
 
+# for CLion
+.idea
+cmake-build-*
+
 # for Xcode
 *.orig
 *.swp