Generalize iterators to allow arbitrary symbolic expressions
Fix iterator bounds checking
change DATA_DIR for Windows %APPDATA%
change from os.path.sep to os.sep
workaround missing %F or %R in Windows strftime
update SeedRandom tests
Merge pull request #106 from sn6uv/WindowsFileDate

workaround missing %F or %R in Windows strftime
Merge pull request #107 from sn6uv/FailedTravisTests

update SeedRandom tests
Merge pull request #103 from ogra/master

Windows APPDATA environment variable.
Merge pull request #101 from sn6uv/PrefixPlusParsing

add AntiMinus symbol to corrent UnaryPlus issue #78
Merge pull request #98 from radford/symbolic-iterators

Generalize iterators to allow arbitrary symbolic expressions
implement RegisterImport
add ExampleData1.txt example data format
begin rewriting Import
add mathics/autoload/format/Text/Import.m
Implement Conditional and Post Importers for RegisterImport
cleanup of RegisterImport
cleanup Import
implement conditionals for Import
Post importers are actually optional and occur seperately to defalt/conditional importers