Merge all changes from branch-3.20. Improvements to the fts5() extension

interface.  Work around a gcc/valgrind bug in the sqlite3_value_pointer()
interface.

FossilOrigin-Name: e0aca7d2c60d9859750a6e98d3e3b87f79779a45920348fc1bda7f1cb93ef996

diff --cc manifest
index 861e2775883d67b27ca159a9c356714a43baa0fa,557aeb9fd7f81a21dc8b0ef73a0f9fa172f17297..8e74bf2aaf113038360c04f6ef908098305160dd
--- 1/manifest
--- 2/manifest
+++ b/manifest
@@@ -1,5 -1,5 +1,5 @@@
- C Merge\sthe\spointer-type\senhancement\sfrom\sthe\s3.20\sbranch.
- D 2017-07-17T13:37:07.979
 -C Interchange\sto\sbranches\swithin\san\s"if"\sstatement\sin\ssqlite3_value_pointer()\nin\sorder\sto\swork\saround\sa\sbug\sin\sgcc.
 -D 2017-07-17T17:46:29.420
++C Merge\sall\schanges\sfrom\sbranch-3.20.\s\sImprovements\sto\sthe\sfts5()\sextension\ninterface.\s\sWork\saround\sa\sgcc/valgrind\sbug\sin\sthe\ssqlite3_value_pointer()\ninterface.
++D 2017-07-17T18:45:23.910
  F Makefile.in eda8bedf08c4c93e2137ef1218b3d3302488c68c2774918de0335a1133aab157
  F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
  F Makefile.msc 20850e3e8d4d4791e0531955852d768eb06f24138214870d543abb1a47346fba
@@@ -1633,7 -1633,7 +1633,8 @@@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a9
  F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
  F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
  F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
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+ R 43a91375009f6b9e40c3c37af47a9695
++T +closed 8a606e4abab4efa03f2e5ffc33d7c5faa3c663f339da87b4ce9f3feed5dc7194
  U drh
- Z 494325537ef296d6ee8662e5f6765eae
 -Z 682f6cb740e4e1e6fe260cc4821cf982
++Z cbc0f4e8a6f497f64de5184412579e6e

diff --cc manifest.uuid
index baaa5c4025dd785bb91938c4a8b7e6e272769144,e3f9fe4e3fca4973c72516682d53e8363775a511..06c894dfd932a75004cfc15796b4debbf9e5e893
--- 1/manifest.uuid
--- 2/manifest.uuid
+++ b/manifest.uuid
@@@ -1,1 -1,1 +1,1 @@@
- 9e8e1c4aa14bcda165b392d1d8af2ce394a56a8e7b67e4c73c742d8da75e73e2
 -8a606e4abab4efa03f2e5ffc33d7c5faa3c663f339da87b4ce9f3feed5dc7194
++e0aca7d2c60d9859750a6e98d3e3b87f79779a45920348fc1bda7f1cb93ef996