Find-GiphyGIF function

Added basic find function
Changed tests to have separate describe blocks
Added Get-GiphyGIF function

Added basic function and tests
Added translate switch to find-giphygif
added api_key= to url construction
Added limit and offset parameters to find function
Added Get-GiphyRandomGIF function and tests
Added get-GiphyTrendingGIF function and tests
Added pms1 file