Fix: Newlines replaced with spaces in botcmd args (#1716)

[zaughon]

Original issue from #1307 remains fixed, but preserves newlines in the args:

[@CHANGE_ME ➡ @errbot] >>> !hello
[@CHANGE_ME ➡ @errbot] [␍] line 1
[@CHANGE_ME ➡ @errbot] [␍] line 2
[@CHANGE_ME ➡ @errbot] [␍] 
cmd = 'hello'
args = 'line 1\nline 2'
Hello! You said: line 1
line 2

# new lines in the middle of a command also works:

[@CHANGE_ME ➡ @errbot] >>> !this is a
[@CHANGE_ME ➡ @errbot] [␍] very long
[@CHANGE_ME ➡ @errbot] [␍] command
[@CHANGE_ME ➡ @errbot] [␍] 
cmd = 'this_is_a_very_long_command'
args = ''


[@CHANGE_ME ➡ @errbot] >>> !this is a
[@CHANGE_ME ➡ @errbot] [␍] very long
[@CHANGE_ME ➡ @errbot] [␍] command
[@CHANGE_ME ➡ @errbot] [␍] test
[@CHANGE_ME ➡ @errbot] [␍] 
cmd = 'this_is_a_very_long_command'
args = 'test'


[@CHANGE_ME ➡ @errbot] >>> !this is a
[@CHANGE_ME ➡ @errbot] [␍] very long
[@CHANGE_ME ➡ @errbot] [␍] command
[@CHANGE_ME ➡ @errbot] [␍] with a lot
[@CHANGE_ME ➡ @errbot] [␍] of test
[@CHANGE_ME ➡ @errbot] [␍] 
cmd = 'this_is_a_very_long_command'
args = 'with a lot\nof test'

[sijis]

Looks good. We didn't consider this case.