Allow static members to be called from type stored in variable.

Supports the following statements:

[Environment]

$path = [System.IO.Path]
$path::GetDirectoryName($project.FileName)
REFACTOR: Remove duplicate code when visiting static members.
TEST: Use TestCase in -eq tests.
Support using $null, bools and strings with -eq operator.
Make -eq case insensitive for strings.
Implement -ge for integers.
Implement -not operator.
Implement -match operator.
Support using indexer on hash table.
Set $matches variable for -match operator.
Support using 'exit' to stop script execution.
Support function parameters in AST.
Add CommentTerminal for delimited comments e.g. <# hello world #>
Merge pull request #150 from alistair/delimited_comments

Add CommentTerminal for delimited comments e.g. <# hello world #>
Implement try catch.

Supports try catch all and allows the use of the error record inside the catch:

try {

} catch {
    Write-Host $_.Exception
}
Merge pull request #151 from mrward/executing-ast

Support a few more statements in PowerShell scripts
Added support for named capture groups in $Matches.
Merge pull request #152 from ygra/match-named-groups

Added support for named capture groups in $Matches.
Fixed numbered/named capturing groups in $Matches.
Merge pull request #153 from ygra/named-groups-bugfix

Fixed numbered/named groups in $Matches