Add desktop_linux_privilege_escalation module
Small bugfix (incorrect filename in data directory)
Removed redundant string "linux_" from exploit name
Converted LD_PRELOAD library from precompiled binary to metasm code.
Removed binary files from pull request (the code has already been converted to metasm)
Fix #4246 - Access payload_exe information correctly

This fixes an undef method 'payload_exe' error. We broke this when
all modules started using Msf::Exploit::CmdStager as the only source
to get a command stager payload. The problem with that is "payload_exe"
is an accessor in CmdStagerTFTP, not in CmdStager, so when the module
wants to access that, we trigger the undef method error.

To be exact, this is the actual commit that broke it:
7ced5927d8807e385c0375a25ef71aef404d3036

Fix #4246
Add initial design draft
Mv KdcRequestBody spec to the correct folder
Add require for EncryptedData
Add initial support for EncryptedData
Add support to decode TGS_REQ body
Require spec_helper
Mark KdcRequestBody encode as unsupported atm
Mark EncryptedData encode as unsupported atm
Add initial support to decode kdc requests
Make specs pass
Add inital support for padata
Add documentation for PreAuthData
Support pa_data parsing on kdc_request
Prefix coding