build(task-runner): add self-documented task runner (#486)

* feat(task-runner): add maskfile.md

`mask` can also act as self-documented task runner
https://github.com/jakedeichert/mask

TODO: add demo.gif on opening this PR

* fix(task-runner): error when basename != dirname

with assumption it only happen on examples/rust

* chore(task-runner): add .gif from pr #486

* fix(task-runner): point $TAURI_* to fixture/*

.gitignore

@@ -83,3 +83,6 @@ Cargo.lock
 # doing this because of how our tests currently (naively) drop the tauri.conf.js in that folder
 # todo: needs a proper fic
 /cli/tauri.js/tauri.conf.js
+
+# doing this because the task-runner (`mask prepare`) will clone gh:tauri-apps/examples
+/examples

Cargo.toml

@@ -3,5 +3,8 @@ members = [
   "tauri",
   "tauri-api",
   "tauri-updater",
-  "tauri-utils"
+  "tauri-utils",
+]
+exclude = [
+  "examples",
 ]

maskfile.md

@@ -0,0 +1,75 @@
+# Shorthand Commands
+
+## prepare
+> Setup all stuffs needed for runing the examples
+
+```sh
+git clone --recursive git@github.com:tauri-apps/examples.git \
+|| (cd examples && git pull origin master; cd ..) 		# always prepare up-to-date examples in case it's already available
+
+export TAURI_DIST_DIR=$PWD/tauri/test/fixture/dist
+export TAURI_DIR=$PWD/tauri/test/fixture/src-tauri
+
+cargo build
+cargo install --path cli/tauri-bundler --force
+cargo install cargo-web 			# used by example rust/yew
+
+cd cli/tauri.js
+yarn && yarn build
+```
+
+## run
+
+![tauri-mask-run-example](https://user-images.githubusercontent.com/4953069/75866011-00ed8600-5e37-11ea-9106-3cb104a05f80.gif)
+
+### run example (example)
+> Run specific example in dev mode
+
+```sh
+source .scripts/init_env.sh
+shopt -s globstar
+
+cd examples/**/$example 2>/dev/null \
+|| cd examples/**/$example/$example 	# workaround for rust/yew/todomvc/todomvc
+
+case "$PWD" in
+*/node/*)
+  yarn && yarn tauri:source dev
+;;
+*/rust/*)
+  cargo web deploy
+  [ $example = `basename $(dirname $PWD)` ] && cd ..
+
+  yarn add tauri@link:../../../cli/tauri.js
+  yarn && yarn tauri dev
+;;
+*)
+  echo unknown project $(dirname $example)/$example
+;;
+esac
+```
+
+## list
+
+### list examples
+> List all available examples
+
+```sh
+find examples/*/*/* -maxdepth 0 -type d -not -path '*.git*' \
+-exec sh -c 'echo $(basename $(dirname {}))/$(basename {})' \;
+```
+
+## clean
+> Remove installed dependencies and reset examples in case something gone wrong
+
+```sh
+cargo uninstall tauri-bundler
+cargo clean
+
+shopt -s globstar
+rm -r **/node_modules
+
+cd examples
+git checkout -- . 	# discard all unstaged changes
+git clean -dfX 		# remove all untracked files & directories
+```