FEAT: added almost-equal for float! datatype.
Merge pull request #843 from qtxie/float-datatype

Float datatype
TESTS: lexer float literals tests added.
FEAT: improved and fixed compiler's lexer for float literals.
Merge branch 'float' of github.com:red/red into float
FEAT: allow simple quotes to be used among fractional part of floats.
FEAT: added ATAN2 native support.
Fixed indentation.
Fixing float-arctangent2 test
Adding .gitignore to ignore test generated files.
Merge branch 'float-doc'

Conflicts:
	runtime/macros.reds
	runtime/natives.reds
Fixing corrupted series-test.red