Allow changing the name for a sequence in the sequence browser.

Allow changing the name for a sequence in the sequence browser.
Doing this required being much more thorough about always using
boost::shared_ptr<>s for GlSequences and Sequences.

When you initalize a shared pointer from something that wasn't specially
allocated for it using new, bad things happen.

This is more of me learning that if one has a temptation to store a reference
don't. Instead use a shared_ptr or similar.