Add destructor functions for the pointer argument (NB: not the type string)

to the sqlite3_bind_pointer() and sqlite3_result_pointer() interfaces.  Use
this new capability to resolve a pointer leak in the custom geometry function
mechanism of the RTREE extension.

FossilOrigin-Name: 5a2340b81faf0a29deb5b7c9a2ba6a7697d646de6cc4e9b2e6e5e6463fa394bd

diff --cc manifest
index 7615139f58f81bc91a8b12139248118a773b6ebb,ac50b3cd700a9514be45190fe03b199968069d49..fe093dce1e09a386fff040bab6acbec829f4040e
--- 1/manifest
--- 2/manifest
+++ b/manifest
@@@ -1,5 -1,5 +1,5 @@@
- C Release\scandidate\s2\sfor\s3.20.0.
- D 2017-07-25T15:12:01.300
 -C In\ssqlite3_bind_pointer(),\sinvoke\sthe\sdestructor\sif\sthe\sbind\sindex\sis\nout\sof\srange,\slike\ssqlite3_bind_blob()\sdoes.
 -D 2017-07-27T16:42:36.805
++C Add\sdestructor\sfunctions\sfor\sthe\spointer\sargument\s(NB:\snot\sthe\stype\sstring)\nto\sthe\ssqlite3_bind_pointer()\sand\ssqlite3_result_pointer()\sinterfaces.\s\sUse\nthis\snew\scapability\sto\sresolve\sa\spointer\sleak\sin\sthe\scustom\sgeometry\sfunction\nmechanism\sof\sthe\sRTREE\sextension.
++D 2017-07-27T17:45:08.840
  F Makefile.in d9873c9925917cca9990ee24be17eb9613a668012c85a343aef7e5536ae266e8
  F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
  F Makefile.msc 02b469e9dcd5b7ee63fc1fb05babc174260ee4cfa4e0ef2e48c3c6801567a016
@@@ -1637,10 -1637,7 +1637,8 @@@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a9
  F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
  F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
  F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
- P 1ca707a4fb8db7aa85430413164265607ce727fc8a5afc3424b3abfb59921b39
- R 8215cf089e6d9a2d7dcbd4ee22b67db3
- T *branch * branch-3.20
- T *sym-branch-3.20 *
- T -sym-trunk *
 -P 601ad6795927fff8c3cc1711a2fd90912499573e94aa5bc8f18cbd4b89778f58
++P f39cb76b3347baba22f2c329e74036710b64620414433a952de8d44da79ba8d9 d6684d2a744e6e04b8796c3b5ecb81c6577728b698c1ab5f4a828b2ac114b8a2
+ R 94d2d6800509c651201392a359c9b77e
++T +closed d6684d2a744e6e04b8796c3b5ecb81c6577728b698c1ab5f4a828b2ac114b8a2
  U drh
- Z b5d895badf8b9b6a24951d6f900b8c5d
 -Z 4d5dc73f23f587970c3fb18e2e41aea7
++Z 1a620a1987be7e7a32507ea55728d87e

diff --cc manifest.uuid
index 1b810724b2895b0d60d00c90faae2b30b6378767,83dd80b63e50a956143b49eb98a64b47034f33bc..935cff7820d75898b08d5843ededdb9464e38136
--- 1/manifest.uuid
--- 2/manifest.uuid
+++ b/manifest.uuid
@@@ -1,1 -1,1 +1,1 @@@
- f39cb76b3347baba22f2c329e74036710b64620414433a952de8d44da79ba8d9
 -d6684d2a744e6e04b8796c3b5ecb81c6577728b698c1ab5f4a828b2ac114b8a2
++5a2340b81faf0a29deb5b7c9a2ba6a7697d646de6cc4e9b2e6e5e6463fa394bd