Merge branch 'PHP-5.6' into PHP-7.0

diff --cc NEWS
index 0528fede4a6dee06e16dd147d5b53dd4aeeab751,1bbb1f4b2b4355a1e04a1306a9b5f02655e14bc8..b9c1c0fe7814d10f12384a417a4ed18de098563f
--- 1/NEWS
--- 2/NEWS
+++ b/NEWS
@@@ -28,10 -24,12 +28,12 @@@ PH
      alphablending). (cmb)
    . Fixed bug #73003 (Integer Overflow in gdImageWebpCtx of gd_webp.c). (trylab,
      cmb)
+   . Fixed bug #53504 (imagettfbbox gives incorrect values for bounding box).
+     (Mark Plomer, cmb)
  
  - Mbstring:
 -  . Fixed bug #72994 (mbc_to_code() out of bounds read). (Laruence, cmb)
 -  . Fixed bug #66964 (mb_convert_variables() cannot detect recursion). (Yasuo)
 +  . Fixed bug #66797 (mb_substr only takes 32-bit signed integer). (cmb)
 +  . Fixed bug #66964 (mb_convert_variables() cannot detect recursion) (Yasuo)
    . Fixed bug #72992 (mbstring.internal_encoding doesn't inherit default_charset).
      (Yasuo)