Changed variables, string concat to expansion.

Added "File" prefix to (now) FileAddedText, FileModifiedText,
FileRemovedText, and FileConflictedText--before, LocalWorkingStatusSymbol
and ConflictedText had the same content by default ("!"), as did
LocalStagedStatusSymbol and ModifiedText ("~").

Changed prompt output of the above variables to use string expansion
rather than concatenation.

Also re-aligned several indentation blocks from 2-space to 4-space
indents. In my opinion, tabs help avoid these issues, but I'll defer to the
lead coder here.

Several lines had nothing but spaces on them, so I removed the spaces
(keeping the empty double line-break).

GitPrompt.ps1

@@ -16,10 +16,10 @@ $global:GitPromptSettings = New-Object PSObject -Property @{
     AfterForegroundColor                        = [ConsoleColor]::Yellow
     AfterBackgroundColor                        = $Host.UI.RawUI.BackgroundColor
 
-    FileAddedText                                   = '+'
-    FileModifiedText                                = '~'
-    FileRemovedText                                 = '-'
-    FileConflictedText                              = '!'
+    FileAddedText                               = '+'
+    FileModifiedText                            = '~'
+    FileRemovedText                             = '-'
+    FileConflictedText                          = '!'
 
     LocalDefaultStatusSymbol                    = $null
     LocalDefaultStatusForegroundColor           = [ConsoleColor]::DarkGreen