Permit custom migration table name to contain '.'

[mirkoperillo]

Currently it is impossible to create a migration table with name master.migrations for example.
The reason is the regexp that check the name

migrate/migrate.go

Line 18 in 507b57a

tableMatcher = regexp.MustCompile(`^[\w]+$`)

This can be useful when a Postgresql DB contains multiple schemas and you want to create migration table in a specific one.

I suggest to add '.' as a valid character
tableMatcher = regexp.MustCompile(^[\w\.]+$)

[markuswustenberg]

Hey @mirkoperillo. That sounds reasonable. Would you like to submit a PR along with a test?

[mirkoperillo]

@markuswustenberg yes, I'm interested.
I'm going to provide a PR asap

[markuswustenberg]

@mirkoperillo Thanks again. 😊 I've just released v0.4.2 where your change is included.