Appveyor Checks for Win OS keep failing

[xavierkamp]

After having updated the Appveyor yml file, the server now is responsive and starts checks. However, it keeps failing because it cannot find the package dependencies.

[xavierkamp]

Possibly linked to packrat package. Loading dependencies from CRAN:

Solves issue, but build freeze after successful tests.

[xavierkamp]

Build freeze is probably linked to the package size. Other package 'parTsForecastR' which is built on top of 'tsForecastR' does not run into this issue. 'parTsForecastR' has less code.