php: bump version

Closes #409.

php-5.2.10 is out, mostly misc bugfixes, one small security fix:

Security Enhancements and Fixes in PHP 5.2.10:

    * Fixed bug #48378 (exif_read_data() segfaults on certain corrupted .jpeg
files). (Pierre)

Key enhancements in PHP 5.2.10 include:

    * Added "ignore_errors" option to http fopen wrapper. (David Zulke, Sara)
    * Fixed memory corruptions while reading properties of zip files. (Ilia)
    * Fixed memory leak in ob_get_clean/ob_get_flush. (Christian)
    * Fixed segfault on invalid session.save_path. (Hannes)
    * Fixed leaks in imap when a mail_criteria is used. (Pierre)
    * Changed default value of array_unique()'s optional sorting type parameter
back to SORT_STRING to fix backwards compatibility breakage introduced in PHP
5.2.9. (Moriyoshi)
    * Fixed bug #47940 (memory leaks in imap_body). (Pierre, Jake Levitt)
    * Fixed bug #47903 ("@" operator does not work with string offsets).
(Felipe)
    * Fixed bug #47644 (Valid integers are truncated with json_decode()).
(Scott)
    * Fixed bug #47564 (unpacking unsigned long 32bit big endian returns wrong
result). (Ilia)
    * Fixed bug #47365 (ip2long() may allow some invalid values on certain
64bit systems).
    * Over 100 bug fixes.

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>