Work on improving CLI parsing

Can now set bool values explicitly with =
Handle multi short flag args like -abc
Add unit tests for CLI parsing
Generate go code to serialize CLI options as a cmdline

TODO: Implement setting of bool vals in C and Go parsing code
TODO: Help/rst output should somehow indicate this feature

gen/go_code.py

@@ -514,10 +514,13 @@ def kitten_clis() -> None:
 
         with replace_if_needed(f'kittens/{kitten}/cli_generated.go'):
             od = []
+            ser = []
             kcd = kitten_cli_docs(kitten)
             has_underscore = '_' in kitten
             print(f'package {kitten}')
+            print('import "fmt"')
             print('import "kitty/tools/cli"')
+            print('var _ = fmt.Sprintf')
             print('func create_cmd(root *cli.Command, run_func func(*cli.Command, *Options, []string)(int, error)) {')
             print('ans := root.AddSubCommand(&cli.Command{')
             print(f'Name: "{kitten}",')
@@ -538,6 +541,7 @@ def kitten_clis() -> None:
             for opt in gopts:
                 print(opt.as_option('ans'))
                 od.append(opt.struct_declaration())
+                ser.append(opt.as_string_for_commandline())
             if ac is not None:
                 print(''.join(ac.as_go_code('ans.ArgCompleter', ' = ')))
             if not kcd:
@@ -550,6 +554,11 @@ def kitten_clis() -> None:
             print('type Options struct {')
             print('\n'.join(od))
             print('}')
+            print('func (opts Options) AsCommandLine() (ans []string) {')
+            for x in ser:
+                print('\t' + x)
+            print('return')
+            print('}')
 
 # }}}