Remove official support for QMake (#3839)

* delet chatterino.pro

* Update documentation

* Update Github Actions config

* Update Cirrus CI config

* Attempt to fix Cirrus CI

* Add changelog entry

* Delete tools/update_filelist.py

It was a QMake-only script? Maybe will need revert + change to CMake or something?

* fix?

* Fuck this linter

* Attempt to clean up build.yml a little

* Add cmaake to install list, remove step for qmake PATH

* Change list entries to always use 1.

Sneaky unrelated change

* These are no longer tests!

* FUCK YOU PRETTIER

* Make BUILDING_ON_LINUX.md simpler

* Get rid of Jenkins

* Get rid of travis

* Remove dupes

* Remove appveyor

* Remove qmake from conanfile

* Try removing explicit qmake path

* Nothing uses the qt style plugins installer anymore

* Update manual linux building instructions

* Update freebsd compilation instructions with a copy paste from the linux instructions

* Remove unused docker files

* Remove linux breakpad build script as it's unused

* Update changelog entry phrasing

* Lint build markdown files

* Change top changelog entry to not be confused as a link

* Skip QtCreator conan setup if conan is disabled

This reduces the amount of warnings & errors Windows users get with
QtCreator

* lint building on linux file

Co-authored-by: Rasmus Karlsson <rasmus.karlsson@pajlada.com>

tools/build-breakpad-linux.sh

@@ -1,14 +0,0 @@
-#!/bin/bash
-cd ../lib/qBreakpad
-
-echo "Updating qBreakpad's breakpad dependency version"
-cd third_party/breakpad
-git checkout 7b3afa9258e58a57ffbeb395d445811f92616ae9
-cd ../../
-
-cd handler
-mkdir build
-cd build
-qmake ..
-echo "Building handler"
-make -j8 && "Successfully built qBreakpad"

tools/docker/build.sh

@@ -1,9 +0,0 @@
-#!/bin/sh
-
-if [ ! -d build-docker-release ]; then
-    mkdir build-docker-release
-fi
-
-cd build-docker-release
-qmake ..
-make -j8

tools/update_filelist.py

@@ -1,29 +0,0 @@
-#!/usr/bin/python3
-
-import os
-import re
-import subprocess
-
-dir_path = os.path.dirname(os.path.realpath(__file__))
-filename = '../chatterino.pro'
-data = ""
-
-with open(filename, 'r') as project:
-    data = project.read()
-    sources_list = subprocess.getoutput("find ../src -path ../src/CMakeFiles -prune -false -o -type f -name '*.cpp' | sed 's_\../_    _g'").splitlines()
-    sources_list.sort(key=str.lower)
-    sources = "\n".join(sources_list)
-    sources = re.sub(r'$', r' \\\\', sources, flags=re.MULTILINE)
-    sources += "\n"
-    data = re.sub(r'^SOURCES(.|\r|\n)*?^$', 'SOURCES += \\\n' + sources, data, flags=re.MULTILINE)
-
-    headers_list = subprocess.getoutput("find ../src -path ../src/CMakeFiles -prune -false -o -type f -name '*.hpp' | sed 's_\../_    _g'").splitlines()
-    headers_list.sort(key=str.lower)
-    headers = "\n".join(headers_list)
-    headers = re.sub(r'$', r' \\\\', headers, flags=re.MULTILINE)
-    headers += "\n"
-    data = re.sub(r'^HEADERS(.|\r|\n)*?^$', 'HEADERS += \\\n' + headers, data, flags=re.MULTILINE)
-
-with open(filename, 'w') as project:
-    project.write(data)
-