Travis/AppVeyor compatibility

Without artifacts/deploying yet, I'm not sure about what the end result will be

.travis.yml

@@ -12,45 +12,22 @@ branches:
   only:
     - master
 
+# This is .NET Core project, we're not building with Mono
+mono: none
+
+# ASF requires .NET Core 2.0+
+# TODO: We should target stable 2.0.0 once it's released
+dotnet: 2.0.0-preview1-005977
+
 # This is our main build matrix
 matrix:
 # We can use fast finish, as we don't need to wait for all builds to mark it as failed/passed
   fast_finish: true
-  allow_failures:
-#   Mono is often broken, we might need to enable/disable allowing failures on as-needed basis
-#   Currently we allow all Mono builds to fail, as it has serious problems, such as random SIGABRTs
-#   This is decent because it allows us to track Mono builds and fix ASF if needed, while not going crazy over false alarms
-#   Ref: https://travis-ci.org/JustArchi/ArchiSteamFarm/jobs/192428388#L2007-L2009
-    - os: linux
-    - os: osx
   include:
-#   We're building ASF with Mono on latest versions of Linux and OS X
+#   We're building ASF with dotnet on latest versions of Linux and OS X
 #   Ref: https://docs.travis-ci.com/user/ci-environment/#Virtualization-environments
     - os: linux
       dist: trusty
       sudo: false
-      mono: weekly
-    - os: linux
-      dist: trusty
-      sudo: false
-      mono: latest
     - os: osx
       osx_image: xcode8.3
-      mono: weekly
-    - os: osx
-      osx_image: xcode8.3
-      mono: latest
-
-# Initialize our envsetup before building, we're adding some extra environment properties there
-before_script:
-  - source mono_envsetup.sh
-
-# Push building notifications on Gitter
-notifications:
-  email: false
-  webhooks:
-    urls:
-      - https://webhooks.gitter.im/e/df82484f12510c3f2516
-    on_success: always  # options: [always|never|change] default: always
-    on_failure: always  # options: [always|never|change] default: always
-    on_start: never     # options: [always|never|change] default: always

appveyor.yml

@@ -13,36 +13,3 @@ build:
   project: ArchiSteamFarm.sln
   parallel: true
   verbosity: minimal
-after_build:
-- cmd: 7z a -mx=9 -mfb=258 -mpass=15 %APPVEYOR_BUILD_FOLDER%\out\ASF.zip %APPVEYOR_BUILD_FOLDER%\out\ASF.exe %APPVEYOR_BUILD_FOLDER%\out\ASF-ConfigGenerator.exe %APPVEYOR_BUILD_FOLDER%\out\config
-artifacts:
-- path: out\ASF.exe
-  name: ASF.exe
-- path: out\ASF.zip
-  name: ASF.zip
-- path: out\ASF-ConfigGenerator.exe
-  name: ASF-ConfigGenerator.exe
-- path: out\ASF-Service.exe
-  name: ASF-Service.exe
-deploy:
-- provider: GitHub
-  tag: $(appveyor_repo_tag_name)
-  release: ArchiSteamFarm V$(appveyor_repo_tag_name)
-  description: '**NOTICE:** Pre-releases are experimental versions that often contain unpatched bugs, work-in-progress features or rewritten implementations. If you don''t consider yourself advanced user, please download **[latest stable release](https://github.com/JustArchi/ArchiSteamFarm/releases/latest)** instead. Pre-release versions are dedicated to users who know how to report bugs, deal with issues and give feedback - no technical support will be given. Check out ASF **[release cycle](https://github.com/JustArchi/ArchiSteamFarm/wiki/Release-cycle)** if you''d like to learn more.\n\n---\n\nThis is automated AppVeyor GitHub deployment, human-readable changelog should be available soon. In the meantime please refer to **[GitHub commits](https://github.com/JustArchi/ArchiSteamFarm/commits/$(appveyor_repo_tag_name))**.\n\n---\n\nASF is available for free. If you''re grateful for what we''re doing, please consider donating. Developing ASF requires massive amount of time and knowledge, especially when it comes to Steam (and its problems). Even 1$ is highly appreciated and shows that you care!\n\n [![Patreon support](https://img.shields.io/badge/Patreon-support-yellow.svg)](https://www.patreon.com/JustArchi) [![Paypal.me donate](https://img.shields.io/badge/Paypal.me-donate-yellow.svg)](https://www.paypal.me/JustArchi/1usd) [![Paypal donate](https://img.shields.io/badge/Paypal-donate-yellow.svg)](https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=HD2P2P3WGS5Y4) [![Bitcoin donate](https://img.shields.io/badge/Bitcoin-donate-yellow.svg)](https://blockchain.info/payment_request?address=1Archi6M1r5b41Rvn1SY2FfJAzsrEUT7aT) [![Steam donate](https://img.shields.io/badge/Steam-donate-yellow.svg)](https://steamcommunity.com/tradeoffer/new/?partner=46697991&token=0ix2Ruv_)'
-  auth_token:
-    secure: QC5gIDMvSpd43EG6qW8d1E3ZHiVU4aR7pbKQonXstjj/JtAABf5S1IbtoY4OsnOR
-  artifact: /.*/
-  draft: false
-  prerelease: true
-  force_update: false
-  on:
-    branch: master
-    configuration: Release
-    appveyor_repo_tag: true
-notifications:
-- provider: Webhook
-  url: https://webhooks.gitter.im/e/6982e3cd9dc9e57b1119
-  method: POST
-  on_build_success: true
-  on_build_failure: true
-  on_build_status_changed: true