#610716 by jhodgdon: Do not dynamically load the PECL stem library. Move checks to separate function, with static caching so it only checks once.

#599058 by Dave Sherohman, jhodgdon: Fix critical issue causing Porter Stemmer to hang in infinite loop with PHP prior to 5.1.0

#493270, #437084, #492892 by jhodgdon: Implement hook from Search by Page module to highlight stemmed keyword matches in search excerpts. Also fixed some minor coding standards issues.

#511930 #437094 #219335 by jhodgdon: Upgrade to the Porter 2 Stemmer algorithm; minimum word size 3 characters. Also updated install instructions and Readme, updated for coding standards, and added SimpleTest tests.