Weekly update for second week of GSoC 2021 community bonding period

From: prathamesh tagore (prathameshtagore_at_[hidden])
Date: 2021-05-31 17:19:51

1. Added remaining pieces of documentation in convolve.hpp in #611 (merged)
(https://github.com/boostorg/gil/pull/611)
2. Added unit tests for verifying boundary manipulation options of 1D
convolution in #612 (open) (https://github.com/boostorg/gil/pull/612)
3. Discussed about tiling implementation for 2D convolution with @Olzhas.