Subject: Fix some typographical and grammatical errors.

CMakeLists.txt

README.build.md

README.coding.md

README.lwsws.md

README.test-apps.md

lib/http2.c

lib/libwebsockets.c

lib/libwebsockets.h

lib/lws-plat-unix.c

lib/private-libwebsockets.h

lib/server.c

lib/service.c

test-server/attack.sh

test-server/test-echo.c

test-server/test-ping.c

test-server/test-server-http.c