sqlite: bump version

Fixes various bugs.

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

package/database/sqlite/sqlite.mk

@@ -4,7 +4,7 @@
 #
 #############################################################
 
-SQLITE_VERSION = 3.6.18
+SQLITE_VERSION = 3.6.20
 SQLITE_SOURCE = sqlite-amalgamation-$(SQLITE_VERSION).tar.gz
 SQLITE_SITE = http://www.sqlite.org
 SQLITE_INSTALL_STAGING = YES