unless you want to hack your esp8266-01, you can just buy a more expensive version of the ESP8266: ESP8266-201 (4$ on Banggood and AliExpress) http://www.banggood.com/it/ESP8266-ESP-201-Remote-Serial-Port-WIFI-Transceiver-Wireless-Module-p-964288.html?p=PU22124098863201603C.
It has the same chipset, but a more developer-friendly board.
Indeed with this version is much easier to make the deepsleep working: the XPD pin (GPIO16) you have to connect to RST to boot the ESP after sleep has its own pin so soldering is not needed any more.
I know there are other solution with ESP12E but their chips and memories are wasted for a such simple application and power comsuption may be higher.