Review the operations with hatching price

[EnchanterIO]

It seems like the operations with attribute p0 are not congruent/correct.

From the first short review: sometimes to calculate the unlocked tokens the contract multiplies with p0 and sometimes divides.

Example:

fundsAllocated() {
    unlockedInternal += _externalAllocated / p0;

claimTokens() {
    uint256 previouslyUnlockedInternal = (paidExternal / p0)

hatchContribute() {
    initialContributions[msg.sender].lockedInternal += contributed * p0;

I think it works only by accident given the p0 is 1 by default. Would be great to review the math here.

[EnchanterIO]

Fixes:

lightstreams-network#5
lightstreams-network#9

[Eknir]

What has lightstreams-network#9 to do with this issue?

[Eknir]

42a601b
Fix