Log message:
Add pkg-config to tools, needed for configure step.
Use MASTER_SITE_SOURCEFORGE in MASTER_SITES.

Log message:
Import Open Text Summarizer to pkgsrc-wip.

The Open Text Summarizer is an open source tool for summarizing texts.
The program reads a text and decides which sentences are important and
which are not. OTS supports many (25+) languages which are configured
in XML files. Several academic publications have benchmarked it and
praised it.