uv_strerror, uv_err_name: check error code

do need to use ZEND_FETCH_RESOURCE_NORETURN macro here

use fetch loop macro

check loop resource type

add docs [ci skip]

uv_ref and uv_unref supports uv_loop resource

update docs [ci skip]

update readm [ci skip]

remove unused variable

update docs [ci skip]

remove needless semicoron

update TODO [ci skip]

update readme [ci skip]

add util function: uv_handle_type

add uv_guess_handle

update docs [ci skip]

fixing markdown [ci skip]

add several function docs [ci skip]

add uv_poll docs [ci skip]

add uv_poll_init_socket

update .gitignore: avoids test output

adjust poll example [ci skip]

do not free here

uv_fs*: callback parameter `fd` passes given PHPs stream, socket or file descriptor.

adjust fs_poll sample