make exclude environment files work on multiple OS

[bcwu]

Description

Fixes #285

discovered that --exclude glob patterns do not work on Windows, fix is outside of the scope of this PR but issue is logged as follows:
#320

[kgartland-rstudio]

Verified that we now exclude proper folders like .git by default on Windows, but the --exclude flag still doesn't work properly.

> tree
C:.
|--.git
|--ignore_me

rsconnect write-manifest dash ./ --exclude ignore_me

yet ignore_me is still in the file list in the manifest while .git is not.

[kgartland-rstudio]

I'm still having some issues with this.

test case:
single sub-folder with a file in it:
ignore-folder/sub-file.txt

command:
rsconnect write-manifest dash ./ --exclude ignore-folder

The manifest created contains the ignore-folder:

The following command works in this scenario:
rsconnect write-manifest dash ./ --exclude ignore-folder/*

test case:
single sub-folder with an additional sub-file and sub-folder and file in it:
ignore-folder/sub-file.txt
ignore-folder/sub-file2.txt
ignore-folder/sub-folder

command:
rsconnect write-manifest dash ./ --exclude ignore-folder/*

error:

It seems if there are multiple files or folders in the excluded folder, it will error with the above failure.

[kgartland-rstudio]

Confirmed that using the --exclude flag works on windows now with both files and folders with and without subdirectories.

It also ignores folders and files that match our exclusion list:

.Rproj.user
.env
.git
.svn
.venv
__pycache__
env
packrat
renv
rsconnect-python
rsconnect
venv