Fix build on amd64 Gentoo

[0181532686cf4a31163be0bf3e6bb6732bf]

This should fix #3 and #4 (worked for me)

[unbornchikken]

This change will break toolset version detection when format is just x.y instead of x.y.z. I believe [0-9]+\\.[0-9]+(?:\\.[0-9]+)? would be the correct form. Could you try this at your side?

[unbornchikken]

Dunno what I have approved, this new UI kinda confusing. @lyssdod could you try that regex at your side?

[0181532686cf4a31163be0bf3e6bb6732bf]

@unbornchikken Thanks! After some testing I've added correct regex to handle both x.y.z and x.y compiler versions

[unbornchikken]

On.

[0181532686cf4a31163be0bf3e6bb6732bf]

Cool, thanks!