0.2.0

This is the second alpha release of the shell. It brings a lot of new features and bugs. :) Below are changes since the last version:

Added

• Checks for valid name and path during creating or editing the shell's aliases
• Checks for valid name and path during creating or editing the shell's
  environment variables
• When there is partial input, looking in the shell's history returns the first
  command which starts with the input
• Ability to insert characters into the current input of the user
• Ability to move between start and end of the current input of the user with
  Home and End keys
• Simple Tab completion for command with names of files and directories
• Coloring the user entered command on green when valid and red on invalid
• Ability to use environment variables inside the shell's environment variables

Changed

• Updated README.md
• Updated adding a new alias form
• Updated editing an existing alias form
• Updated look of list of available aliases, help entries, showing last
  commands from shell's history, list of shell's options, list of environment
  variables, showing the selected alias details, list of shell's options
• Updated adding a new variable form
• Updated editing an existing variable form

Fixed

• Merging commands with || in aliases doesn't work properly
• Information about unknown help topic
• Parsing aliases arguments when the user input contains $ sign
• Handling aliases arguments with whitespaces