Test case for #1683
phalcon_session_write_close()
Use session_write_close() in Phalcon\Session\Adapter::__destruct()

(cherry picked from commit cfd1909ce503b118464bc67085c381ed85cb8ef8)
Fix #1723

(cherry picked from commit ec52cdbc6f13e632c0c1eb64d711c1049775fc76)
Test case for #1723

(cherry picked from commit 64e0ada3def45b73b2943fc07cb26c78793250c4)
Updated CHANGELOG
Regenerated build/
Merge pull request #1727 from sjinks/1.2.5

[1.2.5] Test case for #1683 + bug fixes