Minor help improvements

Author: screamerbg

README.md

@@ -527,13 +527,12 @@ There are various options to `mbed sterm`:
 You can also set default port, baudrate and echo mode using the `TERM_PORT`, `TERM_BAUDRATE` and `TERM_ECHO` Mbed CLI configuration options.
 
 The following shortcuts are available within the serial terminal:
-- Quit: `CTRL+C` or `CTRL+J`
-- Reset: `CTRL+B` or `CTRL+R`
-- Echo toggle: `CTRL+E`
-- Terminal information: `TAB` or `CTRL+I`
-- Help: `CTRL+H`
-- Menu: `CTRL+T`
-- Change baud rate: `CTRL+T+B`
+- CTRL+B - Send Break (reset target)
+- CTRL+C - Exit terminal
+- CTRL+E - Toggle local echo
+- CTRL+H - Help
+- CTRL+T - Menu escape key
+- _Even more shortcuts are available through the Menu shortcut. Check the help within the serial terminal (CTRL+H).__
 
 To automate things, you can also add the `--sterm` option to `mbed compile -f` to compile a new program, flash the program/firmware image to the connected target and then open serial terminal to it's COM port:
 

mbed/mbed.py

@@ -2390,7 +2390,7 @@ def status_(ignore=False):
     dict(name='--build', help='Build directory. Default: build/'),
     dict(name=['-c', '--clean'], action='store_true', help='Clean the build directory before compiling'),
     dict(name=['-f', '--flash'], action='store_true', help='Flash the built firmware onto a connected target.'),
-    dict(name=['-s', '--sterm'], action='store_true', help='Open serial terminal after compiling. Can be chained with --flash'),
+    dict(name=['--sterm'], action='store_true', help='Open serial terminal after compiling. Can be chained with --flash'),
     dict(name=['-N', '--artifact-name'], help='Name of the built program or library'),
     dict(name=['-S', '--supported'], dest='supported', const=True, choices=["matrix", "toolchains", "targets"], nargs="?", help='Shows supported matrix of targets and toolchains'),
     dict(name='--app-config', dest="app_config", help="Path of an app configuration file (Default is to look for 'mbed_app.json')"),