Beta 0.6

Changelog:
https://pact-util-lib.readthedocs.io/en/beta_0.6/deployed.html#version-0-6

Deployed on-chain:
util-lists: 5dyAhqMGH4IM_q2S7RQ_N2ZKvko8HPXFQZlprsATcBc
util-strings: dQ-CDwgBjgtVmmAWZWVVHNGMNPFZuDy2drGb-Bk3MxE
util-math: ub6UFAqyTQ8dVpy6zK4-rNG-W6hqHwS-NX_bfCFGLVc
util-random: od06XLD2aQzeFoasShObwYCWVTqgx-09IEL0fbksoFM
util-time: iY4_6feELzTLXe7H5qzRuXi8tiWhpXgtKGB74JjW2Fk
util-zk: idjgCDWYgW08IzxGxhsZv-8jX15TMw9bQX7PrpeU0TU