library: Clarify API usage regarding NULL PIN values

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Create a securid_unix_exp_date() helper function

This will be called from the library code too, so we might as well put
the formula in a common place.

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
jni: Add set_* helper functions for populating new objects

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
library: Add stoken_get_info() call

This allows callers to query the token's serial number and expiration
date.

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
gui: Enable Alt-C and Alt-Q mnemonic accelerator keys

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
gui: Add --small option to conserve desktop space

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Update changelog

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
desktop: Change description to improve clarity

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
debian: Update symbol list

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>