Fixed line wrapping for the "long help" content in LLDB commands. Content is...

Fixed line wrapping for the "long help" content in LLDB commands.  Content is now dynamically wrapped for the column width of the current terminal.  Lines that begin with whitespace will be indented identically on subsequent lines to maintain formatting.

Existing commands supplying this type of help content have been reworked to take advantage of the changes.  In addition to formatting changes, content was changes for accuracy and clarity purposes.
    
<rdar://problem/21269977>

llvm-svn: 242122