Log Message:
Changes 1.2.5:
* Added append-mode to #capture: use #capture >file-name
* Cleaned #spawned commands interface: text they print on
  standard output *MUST* terminate with a newline ('\n')
  in order for powwow to execute it.
* Fixed missing #include <time.h> in main.h.
* Fixed broken matching of #mark patterns starting with $
* Added the following user-contributed patches:
  * Put also 1-char lines into history;
  * Do not capture/movie data coming from spawned commands;
  * Fixed a bug in command parser.