Added Init config variable.

[scudette]

When the config file specifies the Init option, the initialization
function will be named that (by default it is init() ).

Users can specify an exported name which needs to be explicitly
called. This allows initialization to be explicit to avoid doing it in
cases where it is not needed.

[scudette]

Ref: #45

[UnnoTed]

This solution raises a problem in spread mode because theres a init function in each file, renaming it will cause a name collision.

[scudette]

Does it make sense to put all the init functions in the same file - even in spread mode? Maybe an init.go which takes care of all initialization - the actual string definitions can be kept in spread files.

[UnnoTed]

Yes, that'll work, just remove the spread condition from:
https://github.com/UnnoTed/fileb0x/blob/master/template/files.go#L11
https://github.com/UnnoTed/fileb0x/blob/master/template/files.go#L85

then remove init() and imports from:
https://github.com/UnnoTed/fileb0x/blob/master/template/file.go