TabExpansion2

The script replaces the built-in function TabExpansion2, creates the table
TabExpansionOptions, and does nothing else. Initialization is performed on
the first code completion via profiles *ArgumentCompleters.ps1.

$TabExpansionOptions consists of empty entries:

CustomArgumentCompleters = @{}
NativeArgumentCompleters = @{}
ResultProcessors = @()
InputProcessors = @()

Initialization via profiles. When TabExpansion2 is called the first time it
invokes scripts like *ArgumentCompleters.ps1 found in the path. They add
their completers to the options.

TabExpansion2.ps1 (with extension if it is in the path) should be invoked
in the beginning of an interactive session. Modules and other tools on
loading may check for existence of the table and add their completers.

Any found profile and completer issues are written as silent errors.
Examine the variable $Error on troubleshooting.

Extra table options:

IgnoreHiddenShares
$true tells to ignore hidden UNC shares.

LiteralPaths
$true tells to not escape special file characters.

RelativePaths
$true tells to replace paths with relative paths.
$false tells to replace paths with absolute paths.

Consider to use Register-ArgumentCompleter instead of adding completers to
options directly. In this case *ArgumentCompleters.ps1 are compatible with
v5 native and TabExpansionPlusPlus registrations.

Consider to use Register-InputCompleter and Register-ResultCompleter
instead of adding completers to options directly.