docs: design: fix some fixes
doc: fix forward reference about ghost pads

https://bugzilla.gnome.org/show_bug.cgi?id=711089
pwg: rename the "samplerate" variable to make example code compilable

In one of the examples about gst_my_filter_setcaps() there is a variable
declared as "rate", but then the name "samplerate" is used when setting
the caps.

Use the name "rate" everywhere in gst_my_filter_setcaps().

https://bugzilla.gnome.org/show_bug.cgi?id=710876
utils: Add some attributes and reorganize code to fix compiler warnings

gstutils.c:3659:41: error: format string is not a string literal
[-Werror,-Wformat-nonliteral]
    gchar *expanded = g_strdup_vprintf (stream_id, var_args);

https://bugzilla.gnome.org/show_bug.cgi?id=710621
docs: fix common typos emited/eachother/...
gst-launch: fix potential uninitialized variable warning

https://bugzilla.gnome.org/show_bug.cgi?id=710758
parse: Make the FATAL_ERRORS flag also work without a GError

Also add a unit tests
baseparse: print proper variable in debug statement
baseparse: try first frame pts and dts for a valid start timestamp
basesrc: mind boggling wrap when comparing offsets
segment: resurrect sanitizing start and stop for seeking
memory: explicitly cast to GstLockFlags to avoid compiler warnings