Bash completion script, list-projects, list-contexts commands.

* list-projects lists all the projects in the repo.
* list-contexts lists all the context in the repo.
* Created a bash completion script to allow auto-complete for GTD.

resources/etc/bash_completion.d/gtd

@@ -0,0 +1,39 @@
+_gtd()
+{
+    local cur prev topOpts debugOpts logLevels
+    COMPREPLY=()
+    cur="${COMP_WORDS[COMP_CWORD]}"
+    prev="${COMP_WORDS[COMP_CWORD-1]}"
+    topOpts="help process done calendar list-copies new tickler list debug delegate rename-project list-projects list-contexts"
+    debugOpts="state loglevel"
+    logLevels="TRACE DEBUG INFO WARN ERROR"
+
+    case "${prev}" in
+        help)
+            COMPREPLY=( $(compgen -W "${topOpts}" -- ${cur}) )
+            return 0
+            ;;
+        done|list-copies|delegate)
+            COMPREPLY=( $(compgen -f ${cur}) )
+            return 0
+            ;;
+        ls|list)
+            COMPREPLY=( $(gtd list-projects) $(gtd list-contexts) )
+            return 0
+            ;;
+        debug)
+            COMPREPLY=( $(compgen -W "${debugOpts}" -- ${cur}) )
+            return 0
+            ;;
+        loglevel)
+            COMPREPLY=( $(compgen -W "${logLevels}" -- ${cur}) )
+            return 0
+            ;;
+        *)
+            ;;
+    esac
+
+    COMPREPLY=( $(compgen -W "${topOpts}" -- ${cur}) )
+    return 0
+}
+complete -F _gtd gtd