rules 6.x-1.3

This release contains mostly PHP 5.3 and features integration fixes + support for PHP4 has been officially dropped.

changes since 6.x-1.2:
#774250 patch by keinstein: fixed Declaration of rules_data_type_string::get_default_input_form() should be compatible.. warnings that might occur depending on the PHP settings
#674992 patch by colin49 and me: added tokens for rules number variables
#788108 patch by klausi: require PHP > 5.1. Due to a lack of PHP 4 testers, PHP 4 support is dropped.
#814416 patch by drnugent, tim.plunkett and me: fix warnings when using the features integration by removing an unnecessary argument from rules_categories_features_export_render()
#831610 patch by colin49: Number variable token type no longer working with Token 6.x-1.13
#860402 patch by nemchenk and me: fixed warnings when users without any roles set are imported.
#809252 Avoid doubled categories when exporting rules with features
#756888 fixed feature integration to not overwrite existing rules when updating features
#878124 fixed item type invocation and php5.3 warning

Rules forms:
#557892 by gpk: Fixed update routine for setting rules_forms module weight
added an upgrade warning to the Rules Forms module
bug #758000 by klausi: fixed display of form element IDs to also include those from after build