change 'suffix' to 'prefix' in common doc string
asteval: trimmed imported items from numpy
list exported lineshapes
add get_ast_names(ast) function
add ExpressionModel -- user-supplied expression to model
add (initial) doc for ExpressionModel
fix typo
Merge pull request #147 from newville/master

add ExpressionModel(): a Model derived from a user-supplied expression
FIX #151: Replace tuples with lists in setup.py attributes
Merge pull request #152 from ankostis/no_tuple_in_setup

FIX #151: Replace tuples with lists in setup.py attributes
use versioneer for version info, remove  numpy imports from setup.py
Merge pull request #154 from newville/master

use versioneer for version info, remove  numpy imports from setup.py
use py3.4 in upload script