* Set AGENT_TOOLSDIRECTORY in packer template
This was set in the ruby installer but it is referenced elsewhere so I
believe it makes the most sense to have this set centrally in the packer
template to be referenced across multiple scripts.
* Fix typo
* Capitalize env var in ws2016 template for consistency
* Set AGENT_TOOLSDIRECTORY in Initialize-VM.ps1
* Add missing env var for AGENT_TOOLSDIRECTORY in step in ws2016 template
* Remove separate Python installation for Windows
* Remove Python2 symlink creation
* Move install-ruby and install-python to download-toolcache
* Improve download-toolcache for windows
* Small fix in docs for ruby
* V mapetr/test alt toolcache docs (#8)
* Merge Validate-Ruby and Validate-Python with Validate-Toolcache
* Small fix in output
* Small fix in download toolcache output