Quickies for Perforce

Reverting all files [permalink]
```
% p4 revert -c default ...
```
Reverting opened, but unedited files [permalink]
```
 p4 revert -a
```
will revert all files that haven't actually be edited, leaving the edited opened.
(Thanks to TVL for this one)
Turning off the executable bit in Perforce [permalink]
```
p4 edit -t text [file_list] 
p4 submit
```
(Thanks to TVL for this one)