rebrand CLI from "dream" to "invoke"

- rename dream.py to invoke.py
- create a compatibility script named dream.py that execs() invoke.py
- redo documentation
- change help message in args
- this does **not** rename the libraries, which are still ldm.dream.util, etc

ldm/dream/args.py

@@ -1,7 +1,7 @@
 """Helper class for dealing with image generation arguments.
 
 The Args class parses both the command line (shell) arguments, as well as the
-command string passed at the dream> prompt. It serves as the definitive repository
+command string passed at the invoke> prompt. It serves as the definitive repository
 of all the arguments used by Generate and their default values, and implements the
 preliminary metadata standards discussed here:
 
@@ -19,7 +19,7 @@ To use:
      print('oops')
      sys.exit(-1)
 
-  # read in a command passed to the dream> prompt:
+  # read in a command passed to the invoke> prompt:
   opts = opt.parse_cmd('do androids dream of electric sheep? -H256 -W1024 -n4')
 
   # The Args object acts like a namespace object
@@ -64,7 +64,7 @@ To generate a dict representing RFC266 metadata:
 This will generate an RFC266 dictionary that can then be turned into a JSON
 and written to the PNG file. The optional seeds, weights, model_hash and
 postprocesser arguments are not available to the opt object and so must be
-provided externally. See how dream.py does it.
+provided externally. See how invoke.py does it.
 
 Note that this function was originally called format_metadata() and a wrapper
 is provided that issues a deprecation notice.
@@ -120,7 +120,7 @@ class Args(object):
         '''
         Initialize new Args class. It takes two optional arguments, an argparse
         parser for switches given on the shell command line, and an argparse
-        parser for switches given on the dream> CLI line. If one or both are
+        parser for switches given on the invoke> CLI line. If one or both are
         missing, it creates appropriate parsers internally.
         '''
         self._arg_parser   = arg_parser or self._create_arg_parser()
@@ -137,7 +137,7 @@ class Args(object):
             return None
 
     def parse_cmd(self,cmd_string):
-        '''Parse a dream>-style command string '''
+        '''Parse a invoke>-style command string '''
         command = cmd_string.replace("'", "\\'")
         try:
             elements = shlex.split(command)
@@ -478,23 +478,23 @@ class Args(object):
         )
         return parser
 
-    # This creates the parser that processes commands on the dream> command line
+    # This creates the parser that processes commands on the invoke> command line
     def _create_dream_cmd_parser(self):
         parser = argparse.ArgumentParser(
             formatter_class=RawTextHelpFormatter,
             description=
             """
             *Image generation:*
-                 dream> a fantastic alien landscape -W576 -H512 -s60 -n4
+                 invoke> a fantastic alien landscape -W576 -H512 -s60 -n4
 
             *postprocessing*
                 !fix applies upscaling/facefixing to a previously-generated image.
-                dream> !fix 0000045.4829112.png -G1 -U4 -ft codeformer
+                invoke> !fix 0000045.4829112.png -G1 -U4 -ft codeformer
 
             *History manipulation*
             !fetch retrieves the command used to generate an earlier image.
-                dream> !fetch 0000015.8929913.png
-                dream> a fantastic alien landscape -W 576 -H 512 -s 60 -A plms -C 7.5
+                invoke> !fetch 0000015.8929913.png
+                invoke> a fantastic alien landscape -W 576 -H 512 -s 60 -A plms -C 7.5
 
             !history lists all the commands issued during the current session.