Link against system-provided sqlite3.

--- a/Cargo.toml
+++ b/Cargo.toml
@@ -34,4 +34,4 @@
 
 [dependencies.rusqlite]
 version = "0.15.0"
-features = ["bundled", "functions", "unlock_notify"]
+features = ["functions", "unlock_notify"]
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -91,12 +91,6 @@
 checksum = "08c48aae112d48ed9f069b33538ea9e3e90aa263cfa3d1c24309612b1f7472de"
 
 [[package]]
-name = "cc"
-version = "1.0.52"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c3d87b23d6a92cd03af510a5ade527033f6aa6fa92161e2d5863a907d4c5e31d"
-
-[[package]]
 name = "cfg-if"
 version = "0.1.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -256,7 +250,6 @@
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "742b695cbfb89e549dca6960a55e6802f67d352e33e97859ee46dee835211b0f"
 dependencies = [
- "cc",
  "pkg-config",
  "vcpkg",
 ]