3.3.1 (#529)

* makefile wip

* feat: adds Makefile

Adds a `Makefile` for managing build-related tasks.

* chore: updates dependencies

* chore: updates dependencies

* chore: updates bin scripts

- Removes `build_release.sh`
- Places deprecation notice in `build_devel.sh`, as its purpose has been
  superceded by the `Makefile`.

* chore: updates bin scripts

- Removes `build_release.sh`
- Places deprecation notice in `build_devel.sh`, as its purpose has been
  superceded by the `Makefile`.

* fix: Makefile

Makes several corrections and improvements to the `Makefile`:

- Previously, the `ifeq` rules were not behaving as intended, due to
  false assumptions regarding how `make` fundamentally behaves.
  Malfunctioning imperative-style programming has been replaced with
  declarative rules to repair this issue.

- Previously, all release executables were zipped after compilation. In
  order to spare non-Windows users from (possibly) needing to install a
  package to unzip the executables, all non-Windows binaries are now
  compressed with `gzip`. (Windows executables are still compressed with
  `zip`.)

- Removes a bit of needlessly verbosity in several rules and paths.

* chore: updates dependencies

* chore: bumps version to 3.3.1

vendor/github.com/mattn/go-isatty/go.test.sh

@@ -0,0 +1,12 @@
+#!/usr/bin/env bash
+
+set -e
+echo "" > coverage.txt
+
+for d in $(go list ./... | grep -v vendor); do
+    go test -race -coverprofile=profile.out -covermode=atomic "$d"
+    if [ -f profile.out ]; then
+        cat profile.out >> coverage.txt
+        rm profile.out
+    fi
+done