Add hook for player heal

Useful for event plugins, awarding points for healing etc.
Fixed whitespace, camelCase hook name
Fixed silly net.ReadColor indentation
Proper error handling within net.WriteType

Now with tracebacks!
Fixed minor syntax error in angle extension
net.Readtype error handling
Merge pull request #743 from wiox/master

net library error handling improvements + small fixes here and there
Merge pull request #739 from Kamshak/patch-1

TTT: Add hook for player heal