just license added.
[AESH-260] Not load System.getenv() on forge.
Merge pull request #87 from danielsoro/AESH-260

[AESH-260] Not load System.getenv() on forge.
Merge pull request #86 from eprogramming/contrib

just license added.
[AESH-261]
operators should not be parsed inside double or single quotes
[AESH-263]
added pid to ConsoleOperation and CommandInvocation
[AESH-263]
added foreground and background status for processes
[AESH-263]
command should not be able to put themselves in the background and foreground