Misc: Try to avoid evaluating conditions after window unmap & others

- Try to avoid evaluating conditions after window unmap/destruction.
  Unfortunately, frequently this doesn't work due to the asynchronous
  nature of X.

- Add _GTK_FRAME_EXTENTS exclusion rules to compton.sample.conf. Thanks
  to memeplex, hexchain, and others for info. (#189)

- Add debugging option --show-all-xerrors, and other debugging changes.
  Doc update.

man/compton.1.asciidoc

@@ -2,7 +2,7 @@ compton(1)
 ==========
 :doctype:     manpage
 :man source:  compton
-:man version: nightly-20130421
+:man version: nightly-20140419
 :man manual:  LOCAL USER COMMANDS
 
 NAME
@@ -83,6 +83,9 @@ OPTIONS
 *-S*::
 	Enable synchronous X operation (for debugging).
 
+*--show-all-xerrors*::
+	Show all X errors (for debugging).
+
 *--config* 'PATH'::
 	Look for configuration file at the path. See *CONFIGURATION FILES* section below for where compton looks for a configuration file by default.
 
@@ -255,6 +258,12 @@ May also be one of the predefined kernels: `3x3box` (default), `5x5box`, `7x7box
 *--glx-use-gpushader4*::
 	GLX backend: Use 'GL_EXT_gpu_shader4' for some optimization on blur GLSL code. My tests on GTX 670 show no noticeable effect.
 
+*--xrender-sync*::
+	Attempt to synchronize client applications' draw calls with `XSync()`, used on GLX backend to ensure up-to-date window content is painted.
+
+*--xrender-sync-fence*::
+	Additionally use X Sync fence to sync clients' draw calls. Needed on nvidia-drivers with GLX backend for some users. May be disabled at compile time with `NO_XSYNC=1`.
+
 *--dbus*::
 	Enable remote control via D-Bus. See the *D-BUS API* section below for more details.