Update gitignore and clang-tidy

.clang-tidy

@@ -0,0 +1,23 @@
+---
+Checks: >
+  clang-diagnostic-*,
+  clang-analyzer-*,
+  cppcoreguidelines-*,
+  -cppcoreguidelines-special-member-functions,
+  -cppcoreguidelines-avoid-do-while,
+  -cppcoreguidelines-avoid-magic-numbers,
+  -cppcoreguidelines-non-private-member-variables-in-classes,
+  modernize-*,
+  -modernize-use-trailing-return-type,
+  -modernize-concat-nested-namespaces,
+  misc-*,
+  -misc-non-private-member-variables-in-classes,
+  bugprone-*,
+  -bugprone-easily-swappable-parameters,
+  performance-*,
+  readability-*,
+  -readability-identifier-length,
+  -readability-magic-numbers
+
+CheckOptions:
+  misc-include-cleaner.IgnoreHeaders: 'Eigen/.*'

.gitignore

@@ -4,6 +4,8 @@
 __pycache__
 *.pyc
 build/*
+build2/*
+cmake-*
 dist/*
 gsplines.egg-info/*
 *.stats
@@ -15,3 +17,7 @@ compile_commands.json
 tests/CMakeCache.txt
 tests/CMakeFiles/*
 tests/Testing/*
+GPATH
+GRTAGS
+GTAGS
+tags