2016-10-24:
 * if PSTricks is loaded, set linecolor to background or alert color
 * bump version to 2.4

2016-10-04:
 * ensure side-effects (such as incremented counters) of hidden content of the
   "\only" command
 * bump version to 2.3

2016-10-02:
 * "\savebetweenoverlays" command for counters not to be incremented between
   overlays
 * bump version to 2.2

2016-10-01:
 * don't increment the "equation" counter between overlays
 * bump version to 2.1

2016-09-30:
 * "fragileoverlays" environment, providing partial support for verbatim content
 * bump version to 2.0

2016-09-28:
 * initial release
