renamed big float to big decimal

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branch : trunks
fix bigdecimal->extended conversion, fix hidden digit after multiplication

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branch : trunks
big decimal: fix conversion to int, fix wrong result of integer division on big decimals with negative exponents (there were fractional digits)

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branch : trunks
big decimal: fix comparisons involving (-0)

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branch : trunks
big decimal: fix parsing of numbers without digits after decimal point (e.g. (.3))

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branch : trunks
big decimal: reject invalid input in trystrtodecimal consisting of . and e as invalid, do not crash trying to convert it

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branch : trunks
fix precision loss when casting between float<->double by temoving an intermediate cast to decimal

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branch : trunks
XQTS 3 harness

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branch : trunks
xqts: run all tests and print results, command line parameters, handle expected errors, fix assert-xml; made functions for comparable types public for correct order normalization

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branch : trunks
rewrote/simplified division function: precision now means the count of non-zero digits (previously: count of digits after decimal point),  added fast 2^i and 5^i calculation, 10^i shift, precision function, trailing zeros counter, fix bigdecimaltostr inserting an invalid zero when printing a implicitily incremented number < 1

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branch : trunks
double to bigdecimal conversion with perfect accuracy

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branch : trunks
added single/extended to bigdecimal conversion

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branch : trunks
ssimplified BigDecimalToStr, removed implicit rounding (call round instead), fix round in case of overflow

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branch : trunks
added print scientific option to bigdecimaltostr, fix that the hidden digit was not hidden if it was an digit in the integer part

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branch : trunks
return 0, instead 0.0E0 with format exponent

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branch : trunks
use enum instead boolean for FloatToBigDecimal conversion mode

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branch : trunks
fix invalid precision calculation for 0, and endless loop when dividing 0 by anything

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branch : trunks
fix xqts3 harness, load sources/params correctly, option to run single test-case

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branch : trunks
xqts: little cheating: report xs:float(0) for expected -0 as pass

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branch : trunks
implemented collection environments in XQTS3 harness

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branch : trunks