docs: refresh readme + add AUR package; fix: better hostname (+port) validation

[ZinoKader]

Merges #16, #54 and #56

[codecov[bot]]

Codecov Report

Merging #57 (5837974) into master (6a71a11) will increase coverage by 8.69%. The diff coverage is n/a.

Additional details and impacted files

[](https://codecov.io/gh/SpatiumPortae/portal/pull/57?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=SpatiumPortae) ```diff @@ Coverage Diff @@ ## master #57 +/- ## ========================================== + Coverage 31.30% 40.00% +8.69% ========================================== Files 6 6 Lines 230 230 ========================================== + Hits 72 92 +20 + Misses 138 111 -27 - Partials 20 27 +7 ``` | [Impacted Files](https://codecov.io/gh/SpatiumPortae/portal/pull/57?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=SpatiumPortae) | Coverage Δ | | |---|---|---| | [portal/portal.go](https://codecov.io/gh/SpatiumPortae/portal/pull/57?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=SpatiumPortae#diff-cG9ydGFsL3BvcnRhbC5nbw==) | `36.11% <0.00%> (+36.11%)` | :arrow_up: | | [portal/config.go](https://codecov.io/gh/SpatiumPortae/portal/pull/57?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=SpatiumPortae#diff-cG9ydGFsL2NvbmZpZy5nbw==) | `100.00% <0.00%> (+100.00%)` | :arrow_up: | [](https://codecov.io/gh/SpatiumPortae/portal/pull/57?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=SpatiumPortae)