The RecordNode was accidentally starting the timestamp at the
beginning of the event buffer, rather than at byte #4.

Fixes a bug with my previous change that would crash the program if you
tried to change the parameters of a processor without a parameterEditor.

Allows parameters to be set from saved XML and changes the
parameterEditor buttons (currently for discrete parameters only) to
reflect which parameters are currently used by selected and
non-selected channels. This fixes a problem where the buttons would
always show what the last press was rather than the current values for
the active channels (e.g. If you changed the parameters on Channel 2,
and then switched to select only Channel 1, the GUI would incorrectly
indicate that the settings for Channel 2 were active). Additionally,
allows the user to see what parameter values are used for channels not
currently selected.

Some caveats:
- If a source doesn't generate its own timestamps, all timestamps will be
  zero. This is obviously bad, so we need a way to protect this
  from happening.
- If there are multiple timestamps from different sources, they might
  conflict. Again, something needs to be done about this in the near future.
- If only a 32-bit timestamp is given, it needs to be shifted by 8 bits
  to fit in our 64-bit timestamp slot

To run this in the future, install astyle (sudo apt-get install astyle),
then enter the following from the top-level project directory:

astyle --options=astyle.options --recursive "./Source/*.cpp" "./Source/*.h"

This will convert tabs to 4 spaces and ensure that brackets are on
their own lines.

Use the following command to update the copyright year in all files,
starting in the Source/ directory:

find . -type f -print0 | xargs -0
   sed -i 's/Copyright (C) 2012/Copyright (C) 2013/g'

Works like a charm!

Rearrange member initialization in constructors to silence GCC
-Wreorder warnings (-Wreorder is enabled by -Wall).

Signed-off-by: Marti Bolivar <mbolivar@leaflabs.com>

Signed-off-by: Marti Bolivar <mbolivar@leaflabs.com>

- We'll need this functionality exposed to fix other bugs elsewhere,
  so add new SourceNode::tryEnablingEditor().

- Use isReady() instead of dereferencing dataThread directly, since it
  may be NULL.

- Tweak console output to more accurately describe what's happening.

Signed-off-by: Marti Bolivar <mbolivar@leaflabs.com>

Signed-off-by: Marti Bolivar <mbolivar@leaflabs.com>