Update handling of crowdsales and missing bonus amounts

[dexX7]

This pull request

• .. closes Potential overflow in crowdsale participation with indivisible tokens #247 Potential overflow in crowdsale participation with indivisible tokens
• .. closes Potentially inaccurate results in crowdsale participation with indivisible tokens  #248 Potentially inaccurate results in crowdsale participation with indivisible tokens
• .. closes Crowdsale participation amounts may be off by 100000000 #249 Crowdsale participation amounts may be off by 100000000
• .. closes Granted user amount out of bounds when reaching crowdsale limit #251 Granted user amount out of bounds when reaching crowdsale limit

The "inflation" of indivisible amounts for crowdsales is directly moved into calculateFundraiser, where 256 bit wide integers are used, to avoid constraints related to the max. representable amounts.

Instead of recalculating the credited amounts to determine the missing issuer bonus, the totals, which are available via the crowdsale objects, are directly used.

The FP math was removed and replaced with plain 256 bit wide integers calculations.

This update triggers reparsing, to clear the bad persistence data (see #249).

[dexX7]

Updated to "on progress", because this change should not be rushed, due to it's potential impact.

[zathras-crypto]

Reviewed, looks good to me - tested, seems fine, passes all checkpoints.

Nice work :)

[dexX7]

Thanks for the review.

I confirmed that the results on Windows and other plattforms are the same (with 32000 autogenerated test cases). This doesn't necessarily imply the calculations are correct, but that's a different story anyway. At least I'm more or less convinced that issues such as #124 or #222 are history. :)