Update linux stagers for NX compatibility

- Adds a call to mprotect(2) to the reverse and bind stagers

- Adds accurate source for some other linux shellcode, including some
  comments to make it more maintainable

- Adds tools/module_payload.rb for listing all payloads for each exploit
  in a greppable format. Makes it easy to find out if a payload change
  causes a payload to no longer be compatible with a given exploit.

- Missing from this commit is source for reverse_ipv6_tcp
Add nonx stagers for linux

[See #784]
Give ruby Modules that wrap Metasploit modules a name

[#36737359]

active_support/dependencies cannot resolve missing constants in Metasploit
modules because the wrapper module is anonymous.  In order to make the
wrapper module non-anonymous, the module must be assigned to a constant.
Since we don't want modules colliding, the wrapper module needs a unique
name, so use the module lookup name to derive the proper nested module names
to namespace the wrapper module.  All derived modules are nested under
Msf::Modules.  The name derivation handles invalid characters for constant
names such as digits as the first character or non-alphanumeric character.
The invalid constant name characters are converted to their hex value and
prefixed with X, so '-' in a name become 'X2d'.
Refactor Msf::ModuleManager

[Fixes #36737359]

Refactor Msf::ModuleManager into concerns so its easier to understand and
duplicate code can be made DRY.  The refactoring also ensures that when
loading from directories, Fastlibs, or reloading, the wrapper module will
always be named so that activesupport/dependencies will function.
GnuPG Information Gather Module, tested against Linux
Remove 3rd-party libraries from yard files

[#36737359]

Only include ruby source files under lib/msf or lib/rex.
Improved docs for ModuleManager and ModuleSet.
Remove .rvmrc

Remove .rvmrc from source control and add it to .gitignore so it can't
be readded.
Remove unused extend ActiveSupport::Concern

I wasn't using any the features of ActiveSupport::Concern in
Msf::ModuleManager::Reloading, so remove the extend and just include it
as a regular module.
Restructure module_set.rb for easier diff

Taking egypt's advice for making module_set.rb so it will compare
correctly to master branch for diffing.
Fully qualify constants in Msf::ModuleSet

Changed lexical scope when I changed the declaration from module Msf;
class ModuleSet to class Msf::ModuleSet so that constants in Msf would
not automatically resolve.
Remove duplicate reloading message
remove unnecessary parens and better comments

removes unnecessary parens (and yes I confirmed they are properly
paired), and adds some comments regarding this as not being an ideal
solution, but rather a stopgap
Explicitly require 'active_support/concern'

[#36737359]

When starting msfconsole, 'bundler/setup' is not required, the
'msf/env/gemcache' is required instead. Unlike 'bundler/setup' the
msf/env gemcache does not do the automatic requires for gems in the
cache, so explicit requires on 'active_support/concern' is needed to get
ActiveSupport::Concern defined.  (I could have done require
'active_support' to match the behavior of 'bundler/setup', but a smaller
require seemed more appropriate.
Fix return and calling convention in Msf::ModuleManager::Reloading

[#36737359]

Fix the YARD docs to document the return values and make them consistent
with the modules being called.  Ensure the force flag is passed as an
option to load_modules instead of a positional argument.
Fully-qualify Msf constants.

[#36737359]

On Linux, some of the unqualified constants that resolve on Mac OS X,
don't resolve, so to prevent errors (and because I can't justify why the
unqualified constants should resolve on OS X), I'm qualifying all the
Msf constants that are referenced in the code I've refactored.
Use MODULE_SEPARATOR constant

[#36737359]

Replace literal '::' with pre-existing MODULE_SEPARATOR constant that
was created specifically for this purpose.
Reuse Msf::Modules::Loader::Base methods

[#36737359]

Use typed_paths method instead of inlining adding MODULE_EXTENSION and
type directory to module_reference_name.
Merge branch 'feature/redmine-7224-shellcode-cleanup' of https://github.com/jlee-r7/metasploit-framework into jlee-r7-feature/redmine-7224-shellcode-cleanup
fixes: author format, remove meterpreter support, fix ltype