Removed PKG_CONFIG variable in sqlite3.m4, which conflicts the
variable in pkg.m4. Use PKG_CHECK_MODULES instead of hand-crafted
scripts. Renamed SQLITE3_CPPFLAGS as SQLITE3_CFLAGS since
PKG_CHECK_MODULES macro uses latter name.
* m4/sqlite3.m4
* src/Makefile.am
* test/Makefile.am
Use sqlite3_open if sqlite3_open_v2 is not available.
* src/Sqlite3MozCookieParser.cc
* src/Sqlite3MozCookieParser.h
* m4/sqlite3.m4
* test/Sqlite3MozCookieParserTest.cc