Update .gitignore

2 jobs for master in 29 seconds (queued for 1 second)
Status Job ID Name Coverage
  Build
failed #176
cargo:build

00:00:29

 
  Test
skipped #177
cargo:test
 
Name Stage Failure
failed
cargo:build Build There is an unknown failure, please try again
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$ rustc --version && cargo --version
rustc 1.23.0-nightly (f0fe716db 2017-10-30)
cargo 0.24.0-nightly (859c2305b 2017-10-29)
$ cargo build --verbose --jobs 1 --release
error: could not find `Cargo.toml` in `/builds/mnivoliez/DeepVox` or any parent directory
ERROR: Job failed: exit code 1