Add more patterns to .gitignore

.gitignore

+# emacs backup file
 *~
+
+# autotools
+*.la
+*.lo
+*.m4
 *.o
+*.pyc
+.deps/
+.libs/
+INSTALL
+Makefile
+Makefile.in
+autom4te.cache/
+compile
+config.guess
+config.h
+config.h.in
+config.log
+config.status
+config.sub
+configure
+depcomp
+install-sh
+libtool
+ltmain.sh
+missing
+stamp-h1
+test-driver
+
+# test logs generated by `make check`
+*.log
+*.trs

lib/.gitignore

+includes/ngtcp2/version.h
+libngtcp2.pc