Maybe posting here will make them merge the PR: https://github.com/OnionIoT/i2c-exp-driver/pull/15
Compiled packages are available on https://www.dropbox.com/sh/p7mki5nbgyu1tcv/AABPC1HzA848MbEA9RpNiNNva?dl=0
One can install them with opkg install libonioni2c_0.4-2_mipsel_24kc.ipk pyOnionI2C_0.4-2_mipsel_24kc.ipk pyOmegaExpansion_0.4-2_mipsel_24kc.ipk liboniondebug_0.4-2_mipsel_24kc.ipk
Example using modified python library: https://gist.github.com/foxel/a163231293d7cf6f24831b363a91dfe5