xmake v2.1.7 released, fix some bugs and improve some details

原文链接 https://waruqi.github.io/2017/10/13/update-v2.1.7/
注：以下为加速网络访问所做的原文缓存，经过重新格式化，可能存在格式方面的问题，或偶有遗漏信息，请以原文为准。

This release fix some bugs and improve some details. And provide xmake-vscode plugins to integrate vscode editor and xmake.

If you want to known more usage, please see online documents。

Source code: Github, Gitee.

Add add_imports to bulk import modules for the target, option and package script
Add xmake -y/--yes to confirm the user input by default
Add xmake l package.manager.install xxx to install software package
Add xmake plugin for vscode editor, xmake-vscode
Add xmake macro .. to run the last command

Support 24bits truecolors for cprint()
Support @loader_path and $ORIGIN for add_rpathdirs()
Improve set_version("x.x.x", {build = "%Y%m%d%H%M"}) and add build version
Move docs directory to xmake-docs repo
Improve install and uninstall actions and support DESTDIR and PREFIX envirnoment variables
Optimize to detect flags
Add COLORTERM=nocolor to disable color output
Remove and_bindings and add_rbindings api
Disable to output colors code to file
Update project templates with tbox
Improve lib.detect.find_program interface
Enable colors output for windows cmd
Add -w|--warning arguments to enable the warnings output