Currently the solution file written out by the `sln` command uses a
UTF-8 encoding without a BOM. This causes problems when the solution
file contains non-ASCII code points because Visual Studio and MSBuild
will not use a UTF-8 encoding when reading the solution file if the
BOM is omitted.
This commit causes the BOM to always be written when writing the
solution files.
Fixes#8184.
This commit adds support for specifying directories containing a single
project to both the `sln add` and `sln remove` commands.
Additionally, the output from `sln remove` has been improved to not
mention "project references".
Fixes issue #7343.
This commit fixes#6198.
When a project is removed from a solution using the `sln remove`
command, any projects in the solution with a project dependency (note:
this is different from a project reference) on the project should have
the project removed as a dependency.
The fix is to scan the projects in the solution and remove any
dependencies on the projects being removed. If the dependencies section
is empty after the remove, we skip serialization of the section like
Visual Studio does.
