doc: Rename getPluginId/Ns to getPluginById/Ns
doc: A bit more info about the propGet* functions
doc: Filters' parameter maps don't live forever
doc: Add another 4 plugins to the plugin list
doc: Fix typos and stuff
doc: AddBorders, BlankClip default to black, not [0,0,0]
doc: Syntax highlighting for Lut and Lut2's examples

I have no idea why the second example from each file didn't get
highlighted.
doc: Clarification for MaskedMerge
doc: One more useful example for SelectEvery
doc: Calling Transpose twice in a row is slower than nop
doc: Remove mention of multiple cores in Python scripts
stdlib: Fix setBlack function

AddBorders and BlankClip now default to black for float and not-YUV
formats too.
Merge pull request #55 from dubhater/stuff

Documentation updates