mq: don't allow patches with some reserved names
The current list of reserved names includes only mq control files.
Also, reserve names starting with ".hg" (to avoid troubles with
e.g. .hgignore and .hgtags), and with ".mq" (to allow future
extensions).
This should fix
issue841.
#!/bin/sh
hg init a
cd a
echo a > a
hg add -n
hg st
hg add
hg st
echo b > b
hg add -n b
hg st
hg add b
hg st
echo % should fail
hg add b
hg st
hg ci -m 0
echo % should fail
hg add a
echo aa > a
hg ci -m 1
hg up 0
echo aaa > a
hg ci -m 2
hg merge
hg st
echo % should fail
hg add a
hg st
hg ci -m merge
echo % issue683
hg rm a
hg st
echo a > a
hg add a
hg st