logic: indexer command refactoring

* moved SystemHeaderSearchPaths and FramewordSeearchPaths of indexer cxx indexer commands to CompilerFlags section
* added SourceGroupTestSuite to test indexer command generation of all source groups
* removed "compile_commands.json" from gitignore, because a resource file for the tests has this name

bin/test/data/SourceGroupTestSuite/cxx_cdb/expected_output/output.txt

@@ -0,0 +1,24 @@
+SourceFilePath: "src/Test.cpp"
+	IndexedPath: "src/Test.cpp"
+	IndexedPath: "test/indexed/header/path"
+	CompilerFlag: "clang-tool"
+	CompilerFlag: "-fms-extensions"
+	CompilerFlag: "-fms-compatibility"
+	CompilerFlag: "-fms-compatibility-version=19"
+	CompilerFlag: "-isystem"
+	CompilerFlag: "'/include/path/from/cdb'"
+	CompilerFlag: "-D"
+	CompilerFlag: "DEFINE_FROM_CDB=some_value"
+	CompilerFlag: "-std=c++14"
+	CompilerFlag: "/FS"
+	CompilerFlag: "'./Test.cpp'"
+	CompilerFlag: "-isystem"
+	CompilerFlag: "header_search/local"
+	CompilerFlag: "-isystem"
+	CompilerFlag: "test/header/search/path"
+	CompilerFlag: "-iframework"
+	CompilerFlag: "framework_search/local"
+	CompilerFlag: "-iframework"
+	CompilerFlag: "test/framework/search/path"
+	CompilerFlag: "-local-flag"
+	ExcludeFilter: "**/excluded/**"

bin/test/data/SourceGroupTestSuite/cxx_cdb/input/compile_commands.json

@@ -0,0 +1,7 @@
+[
+	{
+		"directory": "src",
+		"command": "clang-tool -fms-extensions -fms-compatibility -fms-compatibility-version=19  -isystem '/include/path/from/cdb'  -D DEFINE_FROM_CDB=\"some_value\" -std=c++14  /FS  './Test.cpp'",
+		"file": "./Test.cpp"
+	}
+]

bin/test/data/SourceGroupTestSuite/cxx_cdb/input/src/Test.cpp

@@ -0,0 +1 @@
+.

bin/test/data/SourceGroupTestSuite/cxx_cdb/input/src/Test.h

@@ -0,0 +1 @@
+.