fixing linters.

Summary:
old version of linters use "lint_engine" instead of "lint.engine"
Some bookeeping in gitignore.
Reviewers: abhishekk

.arcconfig

@@ -5,6 +5,6 @@
   "load" : [
     "linters/src/"
   ],
-  "lint.engine" : "FacebookFbcodeLintEngine", 
+  "lint_engine" : "FacebookFbcodeLintEngine", 
   "lint.engine.single.linter" : "FbcodeCppLinter" 
 }

.gitignore

@@ -5,6 +5,7 @@ build_config.mk
 *.so
 *.so.*
 *_test
+*.arc
 db_bench
 db_stress
 ldb
@@ -13,3 +14,4 @@ leveldb_shell
 manifest_dump
 sst_dump
 util/build_version.cc
+dg_repl_stress

linters/src/.phutil_module_cache

-{"__symbol_cache_version__":8,"b937ad5f80a8bd1156038b730ff56ec5":{"have":{"class":{"FacebookFbcodeLintEngine":71}},"need":{"class":{"ArcanistLintEngine":104,"ArcanistGeneratedLinter":488,"ArcanistNoLintLinter":577,"ArcanistTextLinter":658,"ArcanistPEP8Linter":1227,"FbcodeCppLinter":1715,"PfffCppLinter":1759,"ArcanistSpellingLinter":1875,"ArcanistFilenameLinter":4207,"Filesystem":357,"ArcanistLintSeverity":778}},"xmap":{"FacebookFbcodeLintEngine":["ArcanistLintEngine"]}},"4443484928afb005f585843d07b04190":{"have":{"class":{"FbcodeCppLinter":13}},"need":{"function":{"Futures":1265},"class":{"ArcanistLinter":37,"ExecFuture":934,"ArcanistLintSeverity":1729}},"xmap":{"FbcodeCppLinter":["ArcanistLinter"]}},"02e2a613e371424b2108d2d6cb849d39":{"have":{"class":{"PfffCppLinter":71}},"need":{"function":{"Futures":875},"class":{"ArcanistLinter":93,"ExecFuture":756,"ArcanistLintMessage":1270,"ArcanistLintSeverity":1607}},"xmap":{"PfffCppLinter":["ArcanistLinter"]}}}
\ No newline at end of file
+{"__symbol_cache_version__":8,"b937ad5f80a8bd1156038b730ff56ec5":{"have":{"class":{"FacebookFbcodeLintEngine":71}},"need":{"class":{"ArcanistLintEngine":104,"ArcanistGeneratedLinter":488,"ArcanistNoLintLinter":577,"ArcanistTextLinter":658,"ArcanistPEP8Linter":1227,"FbcodeCppLinter":1715,"PfffCppLinter":1759,"ArcanistSpellingLinter":1875,"ArcanistFilenameLinter":4207,"Filesystem":357,"ArcanistLintSeverity":778}},"xmap":{"FacebookFbcodeLintEngine":["ArcanistLintEngine"]}},"02e2a613e371424b2108d2d6cb849d39":{"have":{"class":{"PfffCppLinter":71}},"need":{"function":{"Futures":875},"class":{"ArcanistLinter":93,"ExecFuture":756,"ArcanistLintMessage":1270,"ArcanistLintSeverity":1607}},"xmap":{"PfffCppLinter":["ArcanistLinter"]}},"4443484928afb005f585843d07b04190":{"have":{"class":{"FbcodeCppLinter":13}},"need":{"function":{"Futures":1265},"class":{"ArcanistLinter":37,"ExecFuture":934,"ArcanistLintSeverity":1729}},"xmap":{"FbcodeCppLinter":["ArcanistLinter"]}}}
\ No newline at end of file