Updated docs/bash

  * big update in project bash: merge all settings from multiple files
    in 'docs/bash/' into one — 'bash.org';
  * updated (TOP)/bash/*, (TOP)/bash_*/*, (TOP)/profile.d/*, removed
    redundant (TOP)/profile.d/l05keychain;
  * added (TOP)/X/xprofile: a special profile for graphical login
    manager;
  * docs/bash/{completion,funcs,interact,login,profile}.org:
    simplification and syntax update, content of these files are merged
    into 'bash.org';
  * bash/environtment.org: small note about what environment variables are.