Bazel improvements (#23)

* make .bazelrc more consistent

* add submodule to gitignore

* add .bazelignore

---------

Co-authored-by: Jeremy Kun <j2kun@users.noreply.github.com>

Author: j2kun

.bazelignore

@@ -0,0 +1 @@
+externals

.bazelrc

@@ -1,4 +1,5 @@
-build --action_env=BAZEL_CXXOPTS=-std=c++17
-build --cxxopt='-std=c++17'
-build --host_cxxopt='-std=c++17'
-test --test_output=all
+common --action_env=BAZEL_CXXOPTS=-std=c++17
+common --cxxopt='-std=c++17'
+common --copt=-fdiagnostics-color=always
+common --test_output=errors
+common -c dbg

.gitignore

@@ -4,6 +4,9 @@ bazel-mlir-tutorial
 bazel-out
 bazel-testlogs
 
+# git submodule
+externals
+
 # cmake related files
 # ignore the user specified CMake presets in subproject directories.
 /*/CMakeUserPresets.json